As biodiversity net gain (BNG) becomes a mandatory part of the planning process across England, developers are increasingly asking: how much do BNG units cost?
It’s a fair question—and an important one. If you’re preparing a planning application under the Environment Act 2021, you’ve probably realised that delivering a 10% gain in biodiversity can mean off-site units, which come with their own price tag. But the cost of BNG units can vary significantly depending on a range of factors—from location and habitat type to supply and demand in the area.
In this comprehensive guide, we at The BNG Guy will walk you through the key pricing factors, what to expect when budgeting for BNG units, and how to secure the best value while meeting your planning obligations. Whether you’re a seasoned developer or new to the BNG process, this article is your go-to resource.
What Are BNG Units?
BNG units are a way of quantifying biodiversity improvements. One BNG unit represents a measurable uplift in biodiversity, calculated using Natural England’s Biodiversity Metric. Under the rules introduced by the Environment Act, developers must show that their project will result in a 10% net gain in biodiversity.
There are three types of BNG units:
- Habitat Units – General terrestrial habitats like grasslands or woodlands.
- Hedgerow Units – For linear features such as native hedgerows.
- River Units – For watercourses and associated riparian habitats.
So, How Much Do BNG Units Cost?
Let’s get to the point. As of 2025, the cost of BNG units in England generally falls within the following ranges:
| BNG Unit Type | Low-End Cost (per unit) | High-End Cost (per unit) |
|---|---|---|
| Habitat Units | £10,000 | £35,000+ |
| Hedgerow Units | £500 | £1,500+ |
| River Units | £40,000 | £100,000+ |
But before you plug these numbers into your development appraisal, remember: these are just averages. The true price of BNG units is shaped by a mix of supply and demand, habitat scarcity, geographic location, and the delivery mechanism—whether it’s a private landowner, local authority, or government scheme.
Key Factors That Influence BNG Unit Prices
1. Location, Location, Location
BNG units are more expensive in areas where biodiversity is under pressure or where land is scarce. For example, developers working in densely built-up urban areas like London or Manchester may find it harder (and more expensive) to source units locally.
2. Habitat Type and Distinctiveness
High-distinctiveness habitats such as ancient woodland or lowland meadows are far more valuable than low-distinctiveness habitats like modified grassland.
Here’s a rough breakdown:
- Low distinctiveness: £10,000–£15,000/unit
- Medium distinctiveness: £20,000–£25,000/unit
- High distinctiveness: £30,000–£35,000+/unit
3. Availability of Local Supply
If your development is in an area with multiple habitat banks already delivering biodiversity units, competition helps keep prices reasonable.
4. Time Sensitivity
Got a tight planning deadline? You may have to buy from the first provider with available credits, regardless of cost. Planning ahead gives you more negotiating power and choice.
5. Delivery Model
BNG units are sold through various channels:
- Private Habitat Banks – Often competitive but may have a limited geographic scope.
- Local Planning Authorities – Some councils offer their own units but tend to price them conservatively.
- Government’s Statutory Credit Scheme – This is a last-resort option and is deliberately priced high:
- Habitat units: £42,000 each
- Hedgerow units: £650 each
- River units: £110,000 each
Additional Costs to Consider
When calculating the real cost of BNG units, it’s not just about the headline price. You’ll also need to consider:
- Legal agreements (s106 or conservation covenants)
- Monitoring and reporting (usually over 30 years)
- Ecological consultancy fees
- Brokerage or admin costs
How to Get the Best Value for Your Project
1. Start Early
Talk to your ecologist and local authority as soon as possible. Early action gives you more control over costs.
2. Work With a Specialist (Like Us!)
At The BNG Guy, we specialise in helping developers find cost-effective, compliant solutions.
3. Consider On-Site First
Sometimes, small habitat enhancements can help reduce the need for off-site units.
4. Explore Habitat Banking Options
We work directly with habitat banks across the country and can offer competitive access to available units.
5. Plan for 30 Years
Make sure your chosen provider has solid long-term maintenance and monitoring plans.
Comparing BNG Unit Costs vs. Government Credits
Example:
- Shortfall: 4 habitat units
- Government cost: 4 x £42,000 = £168,000
- Private bank cost: 4 x £25,000 = £100,000
Potential saving: £68,000
Real-World Examples
Urban Residential Development – Birmingham
- Requirement: 5 habitat units
- Local unit cost: £32,000/unit
- Saved over £60,000 by reducing off-site needs to 3 units
Rural Commercial Site – Cannock Chase
- Requirement: 10 habitat units
- Cost: £17,500/unit via local landowner
- Total: £175,000 with full compliance
FAQs
How do I know how many BNG units I need?
Your ecologist will assess this using Natural England’s Biodiversity Metric.
Can I buy BNG units anywhere in the country?
Preference is always local first. Only use government credits as a last resort.
Do I need planning permission to buy BNG units?
No, but legal agreements and registration are required.
Can I create and sell my own BNG units?
Yes! If you own land with biodiversity potential, we can help you set it up.
Why Choose The BNG Guy?
We’re your trusted partner for all things BNG. From sourcing units to managing legal agreements, The BNG Guy makes the whole process easier, faster, and more affordable.
- Direct access to competitively priced BNG units
- Planning and legal support
- Friendly, expert advice
- Quick turnarounds
Conclusion
BNG units are an essential part of the planning process, but they don’t have to break your budget. By understanding the factors that drive pricing and working with a trusted partner like The BNG Guy, you can make informed, cost-effective decisions that support both your development goals and the environment.
So, next time someone asks you “how much do BNG units cost?”, you’ll know exactly what to say—and where to get help.