Homes for London: Emergency measures to unlock housebuilding in the capital
On 23 October 2025, the Mayor of London and the Government announced Homes for London, a package of emergency, radical measures to bolster viability and unblock stalled schemes in the capital. The headline measures include a 50% relief from CIL and a reduction in affordable housing requirements from 35% to 20%.
This article provides an overview of the package, its key proposals and the implications for developers, as well as the likely implementation timelines.
The package at a glance
Targeted relief from CIL
The Government proposes temporary, targeted CIL relief for residential floorspace on eligible brownfield schemes that commence after the relief takes effect and before 31 December 2028. Qualifying schemes would receive a 50% reduction in borough-level CIL where they provide at least 20% affordable housing, with further relief available at higher levels of affordable housing. The relief would not apply to Mayoral CIL or to student and co-living accommodation.
The 50% reduction will provide meaningful relief for eligible schemes, but it is time-limited and will only apply to developments that start before the end of 2028. Developers may therefore wish to review their project timelines to align commencement with the relief window where possible.
Easing design standards in London Plan Guidance
The Mayor and the Housing Secretary propose to withdraw or revise elements of London Plan Guidance (“LPG”) that constrain the density of developments. The proposed changes include:
- Dual aspect: The Greater London Authority (the “GLA”) proposes to withdraw the dual aspect guidance in the Housing Design Standards LPG. While dual aspect dwellings confer benefits, the GLA will update guidance to emphasise discretion where schemes can demonstrate adequate passive ventilation, daylight, privacy and avoid overheating.
- Dwellings per core: The GLA also proposes to withdraw the dwellings per core guidance as restrictive application of this has deterred designs that could accommodate additional dwellings.
- Cycle storage: The GLA intends to reduce cycle parking requirements for residential developments to reflect higher densities of development in London, the growth of dockless cycle and e-scooter hire and to introduce greater flexibility to avoid costly requirements, including off-site provision and contributions in lieu.
A time-limited planning route
A new time-limited planning route will sit alongside the existing Fast Track and Viability Tested routes. Under this route, residential schemes on private land may proceed without an upfront viability assessment where they deliver at least 20% affordable housing, with a minimum 60% of that as social rent and the balance as intermediate tenures in line with London Plan policy. This route will be available until 31 March 2028 or the publication of the revised London Plan, whichever is earlier.
In parallel, the Government intends to clarify that applications under Section 73 of the Town and Country Planning Act 1990 should not be used to revisit fundamental aspects of scheme viability or planning obligations. The approach will be embedded through updates to Planning Practice Guidance and national policy measures, on which consultation is planned.
New Mayoral call-in powers
To strengthen the Mayor’s ability to intervene in applications of potential strategic importance, support housing delivery and maximise densities, the Government proposes to expand the Mayor’s call-in powers as follows:
- Boroughs would be required to refer schemes of 50 plus units where they are minded to refuse the application, enabling Mayoral review without waiting for the existing 150-unit referral threshold to be met.
- The Mayor would be able to call in development of buildings of 1,000 sqm or more on Green Belt and Metropolitan Open Land. Currently, the Mayor can review and direct refusal but cannot take over the decision.
The Government also intends to streamline the call-in procedure by allowing written representations in certain cases, instead of full Representation Hearings, which could cut up to six months from the planning process. Additionally, the Government remains committed to implementing existing provisions enabling the Mayor to make Mayoral Development Orders.
These expanded powers may, however, result in more large schemes, particularly those on sensitive or strategic sites, being called in, which developers should account for when planning their project timelines.
A City Hall Developer Investment Fund
The Mayor will establish a new City Hall Developer Investment Fund (the “Fund”) with an initial £322 million grant allocation for 2026-2027. Building on the Mayor’s Land Fund, the Fund will allow a more interventionist role to unlock and expedite delivery of new homes, including targeted investment to accelerate delivery on sites.
The Government and the Mayor will also collaborate on proposals for the potential New Town locations identified in London and on deploying National Housing Bank finance, including a substantial allocation of low-cost loans for social and affordable housing providers. Further details on the Fund are expected to be provided in due course.
Next steps and timelines
The Government will consult for six weeks from November on CIL relief, the expanded Mayoral call-in powers, the new time-limited planning route and the proposed changes to GLA design guidance. The revised design standards could take effect as early as 2026 through Emergency London Plan Guidance.
CIL relief and the expanded call-in powers will be implemented through secondary legislation, while the proposed procedural changes, including allowing written representations in the call-in procedure, will require primary legislation. Developers should monitor the consultations and legislative timeline closely and ensure these are factored into current and proposed schemes.
If you wish to discuss how this package may affect you, or would like further information, please contact the authors of this article or your usual CMS contact.
This article was co-authored by Eleanor Addinall, Trainee Solicitor at CMS.
