How London's housing emergency package will actually work

The emergency measures first announced in October 2025 are no longer just proposals. With the adopted Support for Housebuilding London Plan Guidance published on 25 March 2026, the package has now moved into implementation. Borough CIL relief and expanded Mayoral call-in powers are still progressing through secondary legislation, but the overall direction is now unmistakable.

That matters because London’s housing slowdown is no longer being treated as something the system might eventually correct on its own. Government and City Hall have shifted from acknowledging the problem to intervening directly, with a package designed to reduce viability pressure, strip out unnecessary planning friction, and help stalled schemes move from permission to construction.

This is also part of a wider change in national planning policy.

The draft NPPF 2025, published for consultation on 16 December 2025 and closed on 10 March 2026, points towards a more directive and standardised system. Where the NPPF 2024 tightened delivery expectations within the existing structure, the draft revised version goes further by separating plan-making policies from national decision-making policies and reducing the scope for local process and policy layering to slow development.

The London package is the capital’s immediate response to that wider shift. It works through five main levers: borough CIL relief, time-limited London Plan Guidance changes, a new time-limited planning route with grant support, expanded Mayoral intervention powers, and the City Hall Developer Investment Fund. Together, those measures reach across the whole development process, from viability and design standards to decision-making and delivery finance.

In this article, we explain what this means for developers by drawing on the official October 2025 policy statement and the final Homes for London package confirmed in March 2026. We break down the pillars of the package, how the new routes work, who qualifies, what support is available, and which deadlines now matter most.

Whether you are revisiting a stalled consent, preparing a fresh planning application, or assessing a new site opportunity, this guide breaks down the pillars of the package, how the new routes work, who qualifies, what support is available, and which deadlines now matter most.

In theory, the Community Infrastructure Levy (CIL) was designed to fund infrastructure without undermining viability. 

In practice, especially in London, it has become a rigid tax that doesn't flex with market conditions, often hitting the exact sites where marginal schemes are teetering on the edge.

The new package acknowledges this systemic flaw. Instead of waiting for each borough to go through the arduous process of revising its CIL schedules, the Government is stepping in with a capital-wide relief measure to fast-track viability restoration.

Crucially, the policy distinguishes between infrastructure funding and affordable housing delivery. 

So, what exactly is changing?

The confirmed offer is a borough-level CIL relief that starts at 50% for qualifying schemes delivering at least 20% social and affordable housing and rises linearly up to a maximum of 80% relief where at least 35% social and affordable housing is provided.

The approach includes specific parameters (now refined after consultation):

The approach is transactional: if developers front-load meaningful, affordable delivery, they get a significant cost saving in return.

But here’s the catch. There are critical geographic and typological exclusions:

This means the relief will have uneven effects. In central boroughs where MCIL is high, total savings may be modest. But in outer boroughs, where land values are tighter and MCIL is lower, the impact on viability could be transformational. 

It is also worth noting that many boroughs are holding large balances of unspent developer contributions (CIL & S106) - raising important questions about whether the existing infrastructure burden on developers is proportionate or effectively deployed.

The government has deliberately avoided a blanket discount by embedding clear eligibility tests, including a minimum liability threshold, excluded land rules, and a targeted viability evidence requirement. The aim is to focus support on schemes that are genuinely marginal, rather than offering relief across the board.

Crucially, where a scheme meets the criteria and follows the process correctly, the stated policy intent is that relief should be granted. The aim is to replace case-by-case bargaining with a more predictable route for qualifying schemes.

Timing, however, is where this becomes strategic. Developers need to align phasing, delivery, and affordable housing commitments with the relief window. Miss it, and the opportunity falls away.

Here’s what we’re seeing on the ground. At Urbanist Architecture, we've witnessed countless schemes stall at the final viability hurdle, with CIL often being the straw that breaks the camel's back. 

This intervention marks a clear shift in how development contributions are being approached. For years, the industry has argued that rigid infrastructure charges can suppress the very schemes that would generate value. What we are now seeing is a more pragmatic response, shaped by the realities of the London housing viability crisis and the need to get sites moving again.

What makes this approach particularly effective is its precision. By targeting borough-level contributions on genuinely marginal schemes, it avoids the perception of a blanket developer subsidy while addressing the real pressure points. In that sense, it is a targeted attempt to unlock delivery without undermining public value.

We are already advising clients with stalled permissions, particularly in outer London boroughs, to revisit their feasibility positions. Many of these schemes were previously written off, but the introduction of borough CIL relief London creates a genuine opportunity to bring them back into play.

The policy is grounded in a stark reality. Affordable housing starts in London fell to just 4,522 in 2024/25, compared with 26,386 in 2022/23, highlighting the scale of the London housing delivery crisis and the widening gap between planning permissions and actual delivery.

That is why the relief is deliberately time-limited. It is designed to create urgency, to move schemes from consent to construction, and to avoid embedding long-term subsidy into the system. The message is simple. If a scheme is marginal, this is the moment to act.

We are particularly interested in the impact this could have on medium-density suburban sites. These schemes have often been caught between rising infrastructure costs and cautious sales values, but this shift in approach may finally help unlock that segment of the market.

Next up: design standards.

The London Plan and its associated design standards have long aimed to ensure quality housing, but in many cases, their rigidity has become a straitjacket. Over time, guidance on dual-aspect dwellings, units per core, and cycle parking has solidified into near-mandatory constraints, often at the expense of viability and site optimisation.

This new package aims to replace that rigidity with a principle-led approach, maintaining quality without dictating form.

Dual aspect remains a quality aspiration, but the adopted package withdraws Standard C4.1 (which encouraged new homes to be dual aspect) and Standard B2.5 (which suggested no more than eight homes per floor accessed by a single core) from the Housing Design Standards London Plan Guidance 2023 to avoid inflexible application.

Developers will now be encouraged to use judgement, provided that homes are well-ventilated, well-lit, and avoid overheating. This opens the door to well-designed single-aspect units, particularly on constrained urban sites or those facing noise or air quality challenges.

Similarly, guidance that discouraged high dwellings-per-core ratios is being rethought. Previously treated as a ceiling, it will now be understood as indicative only.

Boroughs are instructed to support increased dwellings per core where quality and fire safety are maintained. This change enables more efficient design, better NIA:GIA ratios, and fewer circulation spaces eating into viability.

Cycle parking, often an afterthought in policy, has become a space-hungry cost driver. Basement levels, podiums, and ground-floor units have been sacrificed to meet on-plot cycle requirements, even as shared micromobility options have grown.

Cycle parking has also been put on a more pragmatic footing. The adopted package introduces time-limited guidance that allows more flexibility around cycle parking standards and types of cycle parking, explicitly linking decisions to design quality and viability considerations. This guidance is intended to apply until 31 March 2028.

But not everything is up for a change. The minimum space standards are not being relaxed - and rightly so. These benchmarks play a vital role in safeguarding liveability, ensuring that even as we embrace flexibility elsewhere, homes still offer adequate space for everyday life. 

As residential architects working across London, we strongly support the continued enforcement of these standards. They reflect well-established research on wellbeing and usability, and in our experience, they set a baseline that protects residents from the kind of substandard micro-living that undermines long-term housing quality.

This is about more than one-off fixes. The Mayor's office is signalling a wider overhaul of how the London Plan operates, reducing complexity, removing duplication, and streamlining the path from concept to permission.

This represents the most significant philosophical shift in London's design policy in a decade. As architects who have spent years navigating the increasingly prescriptive landscape of London Plan guidance, we see this as a return to first principles: good design should be about outcomes, not compliance.

The dual aspect relaxation is particularly overdue. We've designed schemes where achieving dual aspect on every unit has forced inefficient layouts, oversized cores, and ultimately fewer homes. 

On noisy arterial roads or near railway lines, single-aspect units away from the source of disturbance often provide better living conditions than forced dual-aspect arrangements. The new flexibility will allow us to deploy dual aspect where it genuinely adds value, not as a blanket requirement.

The dwellings-per-core change could be transformative for build-to-rent and affordable housing typologies. I recently worked on a scheme where reducing from nine to seven units per core added £2 million to construction costs, purely to satisfy guidance that had calcified into dogma. With this flexibility, we can return to efficient, elegant solutions that maximise the number of homes without compromising safety or quality.

But here's our challenge to the industry: flexibility requires responsibility. Just because you can squeeze more units per core doesn't mean you should. The test must always be liveability, not just viability. 

At Urbanist Architecture, we'll be using this new freedom to create better homes, not just more profitable ones. The schemes that succeed under this new regime will be those that understand flexibility as an opportunity for innovation, not a race to the bottom.

This may be the most radical shift in planning policy since the introduction of the Fast Track Route. Unlike Fast Track, which rewards meeting established affordable thresholds with an exemption from viability testing, the new time-limited route operates as a full-spectrum intervention.

It offers clear upfront advantages, most notably the ability to secure planning permission without a full viability assessment on eligible private sites. In addition, schemes can access grant funding for affordable homes delivered above the first 10% of units, which are expected to come forward without subsidy, helping to bridge viability gaps and bring marginal schemes forward.

In return, the route embeds delivery discipline from the outset. Rather than relying on multiple review stages, it introduces a single Early-Stage Review aligned with the existing Fast Track approach, triggered where agreed build-out milestones are not met. The emphasis is firmly on turning permissions into delivery rather than allowing schemes to stall.

The route is a direct response to the London housing viability crisis. It takes on risk at the front end to unlock delivery, while ensuring that any improvement in viability is captured later. That balance is what makes this approach both interventionist and credible.

So, who actually qualifies?

The criteria are deliberately tight to target schemes that are truly stuck or marginal:

For Build to Rent (BTR) schemes meeting London Plan policy H11 criteria, the affordable housing element can be provided as intermediate rent, with 30% at or below London Living Rent levels (or as Key Worker Living Rent), and 70% at a range of genuinely affordable rents set in line with the Mayor’s published approach and within the relevant income thresholds.

Public land and certain industrial sites have higher affordable thresholds, typically 35%, but utilities land with major contamination or remediation needs will still be eligible at the 20% baseline.

Clear exclusions apply:

The route is time-limited: it is open to applications submitted and validated by an LPA by 31 March 2028, by which time the next London Plan is expected to have been adopted.

The grant offer is both generous and disciplined:

Benchmark grant rates include:

These are high by London standards, offering real subsidy support. However, every grant must still comply with subsidy control rules, and developers must justify funding relative to risk and cost.

For full details on how to apply for grant funding for affordable housing under the new programme, developers should refer to the GLA’s official funding guidance.

But it’s not just about developers

To make this work, Registered Providers (RPs) and local authorities must be ready and willing to acquire the affordable units.

Only GLA Investment Partners will receive grant funding. And there's a clear expectation that, following the 2025 Spending Review, RPs and councils will step up, delivering more homes, more quickly, and to higher standards.

The document is frank: RP appetite for s106 has declined, not just due to finances, but also quality concerns. Developers are now expected to engage early with RPs and design affordable homes to be genuinely usable, not as bolt-ons or deadweight.

The Early-Stage Review replaces the proposed late-stage gain-share mechanism and sits at the heart of the delivery backstop framework. It has been designed to align seamlessly with the existing Fast Track approach.

At its core, the review kicks in when a defined "substantial implementation milestone" has not been reached within 30 months of planning permission being granted. For referable applications, the LPA or the Mayor can agree a different timeframe. The default milestone is straightforward — construction must have reached the first-floor slab of a defined residential building, or be within the first phase of a phased scheme.

The system is built with flexibility in mind. Boroughs, and the Mayor for referable applications, can agree both a different milestone and a different timeframe where the specific circumstances of a site make this necessary. This includes situations where significant enabling works, remediation, re-provision of an existing use, or Building Safety Regulator Gateway timescales need to be taken into account.

When a review is triggered and a surplus is identified, the rules are clear. The full 100% of that surplus must go to the LPA. This can take the form of additional on-site affordable housing, delivered before a specified proportion of market units are occupied, or as a financial contribution where delivering on-site is not feasible.

Importantly, and mirroring the Fast Track approach, there is no requirement for Mid-Stage or Late-Stage reviews under this route. A five-year long stop date applies across all schemes that follow it, giving everyone involved a clear and defined endpoint.

The policy note is explicit that these measures are intended to apply to both existing consents that are now unviable and to future consents. For stalled schemes with extant permission, the expected sequence is: maximise social and affordable housing first (including exploring grant), factor in the availability of temporary borough CIL relief, and only then amend the scheme if viability challenges remain.

Where amendments are needed, applicants may need a deed of variation to the Section 106 agreement and a Section 73 application for condition changes. The package also signals that where applicants amend schemes in line with the time‑limited route, a full viability assessment is not required.

Let’s cut through the headlines.

This is a carefully calibrated piece of policy design that manages a difficult political trade-off. The shift from 35% to 20% affordable housing will attract criticism, but the reality is more pragmatic. A higher percentage that prevents delivery achieves nothing. A lower threshold that unlocks sites is a direct response to the London housing delivery crisis.

What stands out is the precision. This is not a blanket concession. It is targeted at schemes that are stalled or marginal, where viability has become the barrier to delivery. In that sense, it sits firmly within a wider set of London housing intervention measures aimed at getting real sites moving rather than defending theoretical targets.

Our own analysis of stalled schemes points to a consistent pattern. Sites with 35% obligations are sitting dormant, while those with historic 20 to 25% levels are progressing. This route does not dilute standards. It creates a viable pathway where none currently exists, aligning with the logic behind London housing unlocking viability.

The role of grant is also more significant than many realise. With substantial levels of grant funding available, particularly for Social Rent, the public sector is effectively taking a more active position in delivery. Combined with the 10% nil-grant baseline, developers retain exposure, but the overall risk profile shifts in a meaningful way. This is consistent with the wider direction of travel, where funding is being used to accelerate delivery alongside planning reform.

We are already modelling scenarios where previously unviable schemes could move forward at 25 to 30% affordable housing under this route. In many cases, that is more than would have been achieved through prolonged viability negotiations.

What makes this approach work, both politically and commercially, is the balance between certainty and accountability. The front end is simpler, with no upfront viability on qualifying schemes. But the back end is firmer. Miss agreed build-out milestones and the Early-Stage Review is triggered, with any uplift captured for the public sector. This reflects a broader shift in London housing delivery reforms, where permission is no longer the end point. Delivery is.

We are advising clients to front-load their programmes accordingly.

For existing permissions, this creates a genuine second chance. Schemes that were technically implementable but commercially unviable can now be revisited. Rather than allowing them to lapse or re-entering lengthy renegotiations, there is now a clearer route to delivery. In that sense, this is exactly what the policy is intended to do. Turn paper permissions into real homes.

Planning power is shifting. Until now, the Mayor of London has had a limited arsenal: comment on large schemes, call in a few, and direct refusal. But with boroughs slowing or blocking housing on political grounds, those powers haven't gone far enough.

The new powers aim to fix that. The Mayor will no longer be a distant referee. On more schemes, City Hall will have a direct route to review borough refusals, especially where boroughs are minded to refuse applications that meet the new intervention thresholds.

Two big shifts are now confirmed, with secondary legislation to implement them and a stated commencement in May 2026.

First, a new category of Potential Strategic Importance (PSI) applies to residential development of 50 or more homes where the borough is minded to refuse, triggering a streamlined referral/review process.

Second, development involving more than 1,000sqm floorspace in the Green Belt or Metropolitan Open Land is brought within the Mayor’s call-in scope.

The goal is clear: boroughs cannot quietly kill mid-sized or sensitive schemes without a second opinion. And as the Grey Belt policy evolves, the Mayor will ensure MOL release is done strategically, not piecemeal.

With the Mayor now challenging the blanket protection of London’s Green Belt as “wrong, out-of-date and simply unsustainable,” the implications for developers with land on the urban fringe are profound - especially as strategic reviews begin to open up new opportunities for London Green Belt reform.

This does not mean permissions on MOL will be easy, but it raises the level of decision-making to reflect regional priorities.

Golf courses are a good example of why London needs a more open-minded and strategic approach to land. Many sit within Green Belt or Metropolitan Open Land, so they are not straightforward development opportunities and, under this package, are excluded from the temporary borough CIL relief where they fall within the “excluded land” definition.

But that should not end the conversation. Some golf courses make a limited contribution to openness, public access or environmental value, especially where they are enclosed, inaccessible or weakly related to the planning purposes those designations are meant to serve.

In a city facing an acute housing shortage, well-chosen golf course land in sustainable locations should be considered seriously for development, provided proposals are well designed, infrastructure-led and capable of delivering meaningful public benefit.

City Hall is also being equipped to act faster. Some Mayoral call-ins will be decided through written representations, eliminating six-month hearings for every case. The Mayoral Development Order (MDO) process will be activated in full, crucially without needing borough consent.

These two changes give the Mayor the power to speed up delivery and sidestep local vetoes, particularly valuable for strategic housing zones and major regeneration projects.

As an architectural practice that regularly navigates the politics of planning across multiple London boroughs, we see this as an overdue recalibration of power. The current system allows a single committee in a single borough to veto schemes of regional importance. That's not localism; it's parochialism.

The 50-unit threshold for minded-to-refuse schemes is perfectly pitched. It captures the "missing middle" of development: too small for current Mayoral oversight but too important to be decided purely on local politics. We've seen excellent schemes for 60-80 homes killed by committees more concerned with resident associations than housing need. Now those schemes get a second chance at City Hall.

The Metropolitan Open Land powers are fascinating. MOL has become London's sacred cow, often protected more fiercely than the actual Green Belt. But much of MOL is neither metropolitan in character nor open to public access. 

We know of several sites currently designated as MOL that are actually secure private facilities or degraded scrubland. The Mayor's new powers could enable a strategic review of these anachronistic designations.

The acceleration of decision-making through written representations is equally important. We recently had a client wait eight months for a Mayoral hearing on a straightforward scheme. That delay killed the project's financing. Written representations for suitable cases could cut that to eight weeks.

But here's what really excites us: the MDO powers without borough veto. This could unlock area-wide regeneration in a way that's been impossible since the abolition of the London Docklands Development Corporation. 

Imagine MDOs for the Thames Estuary, or the A406 corridor, or suburban town centres. The Mayor now has the tools to think big. The question is whether he'll use them. 

And thinking big must include re-evaluating land on the edges of London. As housing needs intensify, it’s becoming clear that unlocking strategic, well-chosen Green Belt sites will be essential for long-term delivery. Our analysis on why Green Belt land is essential to addressing the housing shortage sets out the evidence behind this argument.

Even with planning permission in place and grant support available, some schemes still do not progress. Market conditions may not support delivery. Remediation costs can erode viability. Infrastructure constraints can delay implementation.

This is where the City Hall Developer Investment Fund becomes critical. Backed by £324 million of government funding, it allows City Hall to intervene directly through grant, loans, debt or equity to unlock stalled or strategic sites, with priority given to projects that can reach practical completion by summer 2029.

The objective is clear: to move beyond policy and into delivery by targeting schemes that would otherwise not proceed. In doing so, it addresses one of the most persistent issues in the capital, the gap between permission and construction.

This represents a notable shift in role. The Mayor is no longer acting solely as a policymaker, but as an active participant in the market, using capital to accelerate delivery and de-risk complex schemes where the private sector alone would hesitate.

The new fund builds on the success of the Mayor’s Land Fund, which City Hall reported had already started more than 8,000 homes, five years ahead of its 2030 target, supporting major regeneration projects such as Holloway Prison, Old Oak, and NHS surplus sites in Enfield and Haringey.

But where the Land Fund focused primarily on land acquisition, the Developer Investment Fund is designed to go further. It targets viability gaps and delivery risk directly, providing a more active and flexible tool to unlock schemes that would otherwise remain stalled.

There is a bigger picture emerging.

London's housing future won't be solved in boroughs alone. The Government and Mayor will collaborate on New Town opportunities in Greater London, with funding and planning powers aligned. The National Housing Bank, backed by £16 billion, will provide a new source of long-term public finance through guarantees, debt and equity to support housing delivery, including social and affordable homes.

This is a shift toward long-term capital stability, replacing short-term bids with strategic certainty.

The Developer Investment Fund represents a fundamental shift in how the public sector engages with development. This isn't just grant funding or planning support; it's patient capital that can take development risk. That's revolutionary for London.

Here’s where we think the fund could have the biggest impact. We see three transformative applications. 

First, land assembly in fragmented ownership areas. We're currently masterplanning a site split between seven owners. The Mayor could now acquire strategic parcels to unlock the whole. 

Second, abnormal costs on brownfield sites. We know of former industrial sites with £20-30 million remediation costs that kill viability before you've built a single home. 

This challenge is reinforced by the Government’s own analysis of brownfield development values, which highlights the often substantial remediation, clean-up, and infrastructure costs that routinely undermine viability on previously developed land.

The Fund could bridge that gap. Third, infrastructure provision. Too many sites stall because they need a new road, school, or utilities upgrade that nobody wants to fund upfront. The Mayor can now be that first mover.

The £324 million may seem modest compared to the scale of London’s housing need, but if deployed strategically, it could unlock substantially more private investment alongside it. We expect developers, housing associations, and local authorities to focus this funding on three types of opportunity with the highest catalytic potential. 

First, stalled estate regeneration projects, where existing plans have faltered due to viability gaps, decanting challenges, or political complexity. With targeted support for land assembly, enabling works, or early-phase infrastructure, these schemes could be revived and accelerated. 

Second, suburban intensification sites, such as underused car parks, retail forecourts, or garage courts, where small-to-medium scale development is viable in principle but often held back by fragmented ownership or insufficient local infrastructure. Public investment could help unlock these overlooked plots, particularly for SME developers and housing associations. 

Third, industrial-to-residential conversions, especially in outer London, remain a major untapped opportunity. Many of these brownfield sites face prohibitive remediation or servicing costs that derail delivery long before a brick is laid. In such cases, even a modest public-sector injection - particularly when aligned with supportive planning - could unlock stalled sites that have lingered for years.

But here is the bigger opportunity. The sites that benefit most will not only be unlocked for delivery today, they will also lay the groundwork for the next stages of London’s growth. We anticipate that the most effective interventions will be those that resolve immediate barriers while also creating the conditions for coordinated, multi-phase redevelopment.

That’s where the real power of the Developer Investment Fund lies: as first mover capital. By absorbing risk the private sector cannot carry alone, it has the potential to de-risk entire neighbourhoods and catalyse transformation at scale. 

Stakeholders welcomed the announcement, highlighting its potential to unlock stalled schemes and generate significant economic value. Estimates suggest that accelerating delivery in London could contribute up to £40 billion to the wider economy, although industry voices stress that viability remains the central constraint and that further action will still be needed to meet the capital’s 88,000 homes-per-year target.

There is also another tool on the table. The National Housing Bank introduces a new source of long-term public finance through guarantees, debt and equity. For housing associations and local authorities, access to below-market, patient capital could make the difference between maintaining existing stock and delivering new homes at scale.

Zooming out even further, the New Towns agenda offers perhaps the most ambitious frontier of all. London still has space for planned new settlements, particularly in the Thames Gateway and Lee Valley. 

With coordinated planning powers and upfront infrastructure investment, we could finally see the emergence of 21st-century garden cities - ones that take the lessons of 20th-century predecessors and do it better: more sustainable, more integrated, and more deliverable.

So when does all this actually happen?

The London housebuilding support package moved into implementation on 25 March 2026, with the publication of the final policy and the adoption of the Support for Housebuilding London Plan Guidance. This guidance is now a material consideration in planning decisions and is already shaping how boroughs assess applications.

The key components are now either in force or moving quickly toward it. The time-limited planning route is open to applications until 31 March 2028. Design flexibility has been introduced through updated guidance. Changes to the Mayor’s call-in powers are expected to come into force in May 2026 through secondary legislation.

Temporary borough CIL relief is confirmed in principle, with detailed regulations being finalised. The relief will apply to eligible schemes commencing before 31 March 2030, reinforcing the need to move quickly.

At the same time, the City Hall Developer Investment Fund is operational. Funding has been allocated and the programme is now open, targeting stalled sites with priority given to projects capable of practical completion by Summer 2029.

The direction is clear. The system has been reset to prioritise delivery, not delay.

The clear message: alignment, clarity, and speed. No one will be able to say they didn't see this coming.

This is a narrow window with clear rules.

Schemes need to be re-tested quickly. Existing permissions should be reviewed against the new route, particularly where viability has previously stalled delivery. The ability to proceed without a full viability assessment on qualifying schemes creates a clear opportunity, but only if applications are submitted in time.

Phasing and programme strategy now matter more than ever. The interaction between the planning route, CIL relief, and delivery milestones needs to be considered from the outset. Miss the window, and the policy advantage falls away.

For many schemes, this is not about redesign. It is about repositioning projects to respond to the deadlock in London's housing delivery and move them into construction.

The tone from Government and City Hall is unambiguous.

These measures are designed to be used. Boroughs are expected to support policy-compliant schemes. Developers are expected to move quickly. Delivery is the priority.

This marks a clear shift in how housing delivery policy is being applied in London. Permission alone is no longer enough. Schemes that do not progress risk being left behind, while those that align with the new framework will benefit from faster decisions, greater certainty, and, where needed, public-sector capital intervention to support delivery.

The implementation timeline shows how serious this is. Consultations launched in November 2025 and closed in January 2026, with the final package adopted on 25 March 2026.

The focus has now shifted from consultation to delivery. The key questions are no longer theoretical, but practical. How will CIL relief be administered in real terms? What constitutes a “minded to refuse” position that triggers Mayoral intervention? And how will boroughs interpret new design flexibility in practice, particularly where they remain used to rigid standards?

Our advice to the industry is simple. Act early. The framework is now set, and the opportunity lies in how quickly schemes can be repositioned to align with it.

We are particularly focused on ensuring these measures benefit SME developers and housing associations, not just major housebuilders. The diversity of London’s development ecosystem is one of its greatest strengths, yet smaller firms are often the first to be constrained by rising costs and slow-moving planning processes, especially on smaller urban sites.

As the Home Builders Federation recently highlighted, these barriers are already limiting the participation of agile, design-led developers. That is why clarity, consistency, and speed in implementation will be critical. Without that, the risk is that only the largest players are able to respond effectively.

The March 2028 deadline now carries real weight. It provides enough time to bring forward serious schemes, but also creates a clear sense of urgency.

We expect a significant increase in activity through 2026 and 2027 as developers move to take advantage of the new route, CIL relief, and funding support. That will place pressure on boroughs and the GLA to respond at pace. If resourcing does not keep up, delay risks becoming the next constraint.

This package does not solve every issue.

Land values remain stubborn, construction costs are volatile, and skills shortages persist.

It also does not fix the longstanding cost-quality disconnect in new builds, a concern we have seen first-hand frustrate communities and buyers alike. That disconnect continues to undermine public trust in development.

Still, within the bounds of planning and housing policy, this represents the most significant breakthrough in more than a decade.

It marks a shift from standoff to partnership, offering a new contract between the public and private sectors. That shift is reinforced by the published correspondence from the Secretary of State and the Mayor of London, which formally confirmed the final proposed package and set out clear expectations for developers, Registered Providers and London Boroughs to use these measures to maximise delivery.

In return for delivering more housing, more quickly, and with a clearer social dividend, the development industry will receive greater certainty, better tools, and more support.

We encourage every actor in London’s housing ecosystem, from SME developers to housing associations, landowners, local authorities, and design professionals, to engage with these reforms not as a short-term workaround, but as the beginning of a new, high-trust delivery model.

We don’t claim to have all the answers, but our work over the past decade has given us a close-up view of the barriers facing housing delivery in London. From small infill and backland developments to medium-sized brownfield schemes, we’ve seen where progress stalls and why. That’s why we recognise how much of this package speaks directly to the right pressure points.

Even so, the real test lies ahead: how the industry responds. Will developers, local authorities, and registered providers take this chance to reset the pace of delivery? Will we finally see momentum where, for too long, there has been drift?

The stakes could not be higher. London cannot afford another lost decade. With this package, we may finally have the foundation for a better one. But good policy is only the start. It’s how it’s used that will determine whether it leads to real homes on real sites.

At Urbanist Architecture, we stand ready to help our clients unlock these opportunities with the urgency, creativity, and specialist precision they require. The technical details are important, but the bigger picture matters even more. London is open for development again.

The question is not whether to act, but how quickly open-minded developers can move to seize this moment. The most successful teams will be those who see this not as a one-off policy window, but as the blueprint for how London builds its future.