How to source off-site BNG units in London
Tell BNG Sourced by Green Acres BNG your requirement once. Our specialists source potential supply from landowners, habitat bank operators and BNG providers across London and the rest of England, match it to your metric and the trading rules and make the introduction. Free for developers.
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Live supply outlook by unit type
2 registered gain sites in the London covering 41 hectares, with 3 allocations recorded. Most sites by planning authority: Bromley (1), Croydon (1). Counts from Natural England's biodiversity gain site register, updated 4 October 2026. Good means 35 or more registered sites creating area habitat (20 for hedgerow, 8 for watercourse); limited means 15, 8 and 3 or more; scarce is fewer. Outlooks describe the region, not your site; see data and methodology.
Local planning authorities and growth areas
Main authorities in London include the 32 London boroughs and the City of London, with mayoral development corporations at Old Oak and Park Royal and the London Legacy Development Corporation. Development pressure is driven by Opportunity Areas including Old Oak and Park Royal, the Thames Gateway, Brent Cross, Thamesmead and Canada Water, build-to-rent and student housing, logistics on the North Circular and M25 fringe and the Silvertown and Heathrow corridors.
Local Nature Recovery Strategy areas
LNRS areas covering London: London (Greater London Authority). Spatial risk is currently assessed by local planning authority and National Character Area. The government plans to move it to England’s 48 LNRS areas, with no commencement date set when we last checked. For London that would mean supply anywhere within the same LNRS area counting as local, which changes which sites are worth looking at first. Read the LNRS guide.
Typical development pressures
Almost all London development is on previously developed land with little room for on-site habitat and there is very little registered supply inside Greater London. Most schemes therefore buy units from the adjacent Home Counties at the 0.75 multiplier or further afield at 0.5. The brownfield exemption consultation, if adopted, would affect many smaller residential sites in London, but until the government responds they remain in scope.
Sourcing BNG units for a London development, step by step
- Most London sites are previously developed, so the deficit is small and often a fraction of a unit, but there is nowhere to deliver it on site.
- We check the borough and shared NCAs first. The Inner London and Thames Basin NCAs cross borough boundaries, so a neighbouring borough’s site can sometimes be local.
- Options from Essex, Hertfordshire, Surrey and Kent at the adjacent multiplier are typical, with arithmetic shown.
- Allocation and gain plan evidence.
Local context developers ask about
Registered supply inside Greater London is minimal. Opportunity Areas, build-to-rent and student schemes generate steady demand for fractional units. The brownfield exemption consultation would affect many London sites if adopted, but until the government responds they remain in scope; the 0.2 hectare exemption already covers many small infill sites.
Typical habitats and unit types in London
Most London sites are previously developed land with hard standing, amenity grassland and scattered trees. Baselines are low and deficits small, often less than one unit, but open mosaic habitat on previously developed land can appear on long-vacant sites and scores highly. Watercourse units arise on schemes beside the Lea, Wandle, Ravensbourne and other tributaries where channels are modified. Hedgerows are rare; lines of trees are assessed in the hedgerow module.
Other constraints to run alongside BNG
The London Plan’s urban greening factor runs alongside BNG and can be met partly by the same green roofs and planting, though the two calculations differ. Sites near the Lee Valley, Epping Forest and Richmond Park designations face habitats regulations assessment.
Who to involve and when
- Pre-application: ecologist for the metric and urban greening factor, us for adjacent-area supply
- Application: planning consultant for hierarchy statement and draft gain plan
- Post-permission: provider allocation, final gain plan
The multiplier in London
| Where supply sits | Multiplier | Units bought for a deficit of 1 |
|---|---|---|
| Same LPA or National Character Area | 1.0 | 1.00 |
| Adjacent LPA or NCA | 0.75 | 1.34 |
| Elsewhere in England | 0.5 | 2.00 |
London questions
Is there any registered supply inside Greater London?
Very little and what exists is small. The practical answer for most boroughs is supply from the adjacent home counties at 0.75, with the National Character Area occasionally making a site local at 1.0. The 0.2 hectare exemption and the brownfield baseline mean many smaller London schemes have no off-site deficit at all, which the exemption checker will confirm.
Does open mosaic habitat change my deficit?
Often. Open mosaic habitat on previously developed land is high distinctiveness in the metric, so a site that looks like a yard can generate a deficit that must be replaced like for like or better. Your ecologist’s baseline survey decides this; we then source high distinctiveness units, which are scarcer and dearer.
Which LNRS area would my site fall in?
the Greater London Authority leads the London LNRS. Under the current rules the Local Nature Recovery Strategy is a consideration in the metric through the strategic significance multiplier, not a boundary for spatial risk, which still uses the local planning authority and National Character Area. Government has consulted on moving spatial risk to LNRS areas; no commencement date was set when last checked. We track this and will update the region pages when it changes.
What counts as local for a site in London?
A gain site is local, at 1.0, if it is in the same local planning authority as your development or in the same National Character Area, which often crosses council boundaries. Main authorities here are the 32 London boroughs and the City of London. Adjacent means a neighbouring LPA or NCA, at 0.75 and Essex, Hertfordshire, Buckinghamshire, Surrey and Kent are adjacent, so most London supply comes from the home counties at 0.75. Anything else in England is elsewhere at 0.5, so a deficit of 2 units needs 4.
How much do BNG units cost in London?
Indicative unit prices for London schemes reflect home counties supply at the adjacent multiplier, which raises the effective price per unit of deficit by a third compared with a local site. The price per unit matters less than the effective price per unit of your deficit after the multiplier: a local unit at a higher price is often cheaper overall than a distant unit at a lower price. The estimator on the home page and the prices page give dated indicative ranges; only a provider can confirm a price.
How long does sourcing take here?
Typically we come back with options within one working day of receiving your requirement and allocation can follow within a week or two where the provider has registered, unallocated units and your ecologist can supply the metric and gain plan extracts promptly. The slowest steps are usually on the development side: a draft metric that changes or a gain plan submitted late. For phased schemes we can arrange forward allocation so later phases are not left searching.
Are hedgerow and watercourse units available in London?
Hedgerow units are scarcer than area units everywhere and watercourse units scarcer still, because few registered sites create them; the live outlook above shows how many sites in this region do. They cannot be substituted with area units, so a scheme with linear deficits should start sourcing before the planning application rather than after. Typical losses here are developed land and sealed surfaces with low baseline value, but open mosaic habitat on previously developed land can carry high distinctiveness and generate unexpected deficits.
What local constraints sit alongside BNG in London?
brownfield baselines, the urban greening factor in the London Plan and borough-level policies that favour on-site delivery all shape how much off-site demand a scheme generates. These are separate processes from BNG with their own evidence, but they affect which gain sites are suitable and sometimes which providers can help with more than one obligation, so tell us about them when you submit your requirement.
Related: BNG unit prices, spatial risk multiplier, England supply index, all regions.
Need units in London?
Tell us your requirement and we'll start sourcing today.
- One requirement, one point of contact, supply from across England
- Options checked against your metric, the trading rules and the spatial risk multiplier
- Free for developers: where our involvement results in an introduction, the provider pays us an introduction fee
- A specialist in touch, typically within one working day
Free for developers. Your details are only used to source your units.