14 October 2025

 

The Institute of Sustainability and Environmental Professionals (ISEP), has published a new paper on biodiversity net gain (BNG) in England, providing a short overview and key insights regarding the implementation of BNG legislation.

 

BNG is a world-leading mechanism that mandates a measurable 10% gain for biodiversity in the majority of developments across England. The paper reflects on the progress made since BNG's mandatory implementation began in early 2024.

The summary covers ten themes related to BNG, documenting the system's early achievements and the experiences of stakeholders during its first 18 months of operation.

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A core focus is on the practical aspects and market structures supporting BNG. This includes reflections on how BNG is being integrated into development planning and design, and observations concerning the Biodiversity Gain Sites Register, which records land available for off-site BNG provision. The paper examines the emerging market dynamics, such as the pricing and availability of biodiversity units.

The paper also explores the intersection of BNG with broader regional policy, specifically looking at the development and adoption of Local Nature Recovery Strategies (LNRSs) and their role in guiding targeted habitat creation. Furthermore, it briefly outlines different legislative approaches to biodiversity enhancement in other parts of the UK.

The document details the challenges and adaptation requirements faced by Local Planning Authorities (LPAs) in processing BNG applications and securing compliance. It also reviews the legal mechanisms that secure off-site gains for the required 30-year period.

The role of the farming industry is addressed, highlighting how BNG provides opportunities for diversification by enabling landowners to establish habitat banks and earn revenue from providing biodiversity credits.

Finally, the ISEP paper discusses the outlook for BNG. This includes pending legislative changes, such as the introduction of BNG for Nationally Significant Infrastructure Projects (NSIPs), and consultations announced by the Department of Environment, Farming and Rural Affairs (DEFRA) aimed at simplifying the BNG policy for minor, medium, and brownfield developments.

This paper is suitable for local authorities, ecologists, developers, land owners, and anybody interested in the implementation and insights from the development of BNG.

ISEP members can download their FREE copy of the guide here.

Non-ISEP member can purchase the guide here.


Published by:
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Lesley Wilson AISEP

Policy and Engagement Lead

Lesley is Policy and Engagement Lead at ISEP with a focus on the rapidly developing area of biodiversity and natural capital. On behalf of ISEP, Lesley also supports and is a member of the Steering Group of the UK Business and Biodiversity Forum. Lesley has worked in environmental sustainability for 15 years and previously delivered programmes and solutions in sustainability for business at the British Standards Institution, including ground breaking standards in biodiversity net gain and natural capital. Lesley has a qualifications in business management (MBA) and climate change management, and mentors environmental students at the University of Westminster.