An overview of global biodiversity finance

2. Key findings on global biodiversity finance

2.1. Global biodiversity finance flows

Global biodiversity finance from all sources – domestic and international finance from public and private sources – is approximately USD 74.9-92.4 billion per year (equivalent to around 0.07-0.08% of global GDP), based on currently available data. This estimate represents an annual average across available observations for 2023-25. Public domestic expenditure represents the largest component (61-69%). International public and private finance provide smaller but material contributions, accounting for approximately 17-21% and 14-17% of the total, respectively (Figure 1).

While important data gaps and methodological constraints remain, the consistent, time-series data that are available, covering 2018-2025, suggest that public and private biodiversity finance has increased (section 2.5). It is also important to note that the aggregate estimate presented here is not directly comparable with the OECD (2020[3]) estimates, which were based on 2015-17 data, owing to differences in data coverage, underlying reporting methodologies of the country data and the lack of comparable data on private finance (see section 2.5 for further detail).

Figure 1. Biodiversity finance 2023-25 average

Note: Box areas are based on the arithmetic midpoint of the reported lower and upper estimates for visual comparability. These midpoints are illustrative and should not be interpreted as central or expected estimates.

Source: OECD analysis.

2.2. Public domestic biodiversity expenditure

2.2.1. Total estimate of public domestic finance for biodiversity

Public domestic expenditure accounts for the largest share of total biodiversity finance, estimated at USD 46.0-63.5 billion per year, averaged over 2023-25, and is based on the data sources and methodology summarised below. The lower-range estimate reflects an average of annual biodiversity expenditure covering 104 countries, while the upper figure also includes average annual expenditure of approximately USD 17.5 billion reported to the CBD by the European Union (EU). Because some EU expenditure may also have been reported by individual EU Member States as domestic expenditure in their reporting to the CBD, the upper figure is likely subject to some degree of double counting.

The 104 countries included in the compilation account for 61% of the world’s GDP,1 82% of OECD member countries and 74% of the Group of Twenty Nations [G20] member countries by number. The estimate therefore covers many large economies, but it remains incomplete. For example, it excludes India and the United States because 2023-25 data were not identified across the three data sources used in this analysis. The absence of these data is one of the reasons why the estimates of global biodiversity finance presented here should be interpreted as conservative.

Across the 104 countries, domestic public expenditure on biodiversity averages 0.13% of GDP. The median is 0.07%, with the 25^th and 75^th percentiles at 0.02% and 0.13%, respectively. On a GDP-weighted basis, aggregate biodiversity expenditure represents 0.07% of the combined GDP of these countries.

Applying these expenditure-to-GDP ratios to global GDP yields an indicative estimate of global public domestic biodiversity expenditure of approximately USD 75-147 billion per year.2 The lower estimate is based on the GDP-weighted expenditure ratio (0.07% of GDP), while the upper estimate is based on the unweighted average expenditure ratio (0.13% of GDP). These figures should be interpreted with caution, as they assume that countries without available data allocate a similar share of GDP to biodiversity as reporting countries. Consequently, they provide an indication of the possible order of magnitude of global public domestic biodiversity expenditure rather than a measured estimate.

2.2.2. Composition and comparability

The public domestic biodiversity expenditure estimate is derived from three data sources: (i) expenditure reported through National Reports to the Convention on Biological Diversity, (ii) Government Finance Statistics (GFS) expenditure reported under the Classification of the Functions of Government (COFOG) category "biodiversity and landscape protection" (COFOG 05.4); and (iii) Environmental Protection Expenditure Accounts (EPEA) expenditure reported under the Classification of Environmental Purposes (CEP) category "biodiversity and landscape protection" (CEP 0502). The latter two data sources are based on international statistical classifications and therefore provide a more standardised basis for comparison across countries. The estimate gives priority to data reported through CBD National Reports, and uses the other data sources to address gaps in country-level observations.

An alternative approach would be to select the highest value across the three datasets. This approach is also undertaken here because some countries explicitly stated in the CBD National Reports that the domestic public expenditure reported was limited to a few programmes or a small share of overall biodiversity finance. This alternative approach increases the overall estimate for public domestic expenditure to USD 48.4-65.9 billion (compared with USD 46.0-63.5 billion per year under the approach that prioritises data reported through the CBD National Reports). The relatively small difference between the two estimates suggests that the overall results are not highly sensitive to the choice of data source.

The domestic public finance estimate includes a combination of direct expenditure and indirect biodiversity-related expenditure reported to the CBD, and primary purpose expenditure reported to GFS-COFOG and EPEA-CEP. Countries reporting through CBD National Reports vary in their treatment of the categories on direct and indirect: some report direct expenditure only (with a subset reporting primary purpose expenditure from GFS-COFOG and EPEA-CEP), others report both direct and indirect expenditure, while some do not specify the distinction (see section 4.1.1 for further detail). Furthermore, some countries apply coefficients to indirect expenditure while others do not specify. Given these differences, the incomplete availability of indirect expenditure data, and the absence of data for some countries, the estimate should be interpreted as an order-of-magnitude assessment rather than as a precise minimum and maximum range.

2.3. Public international finance for biodiversity

2.3.1. Total flows of public international finance for biodiversity

International public expenditure on biodiversity is estimated at USD 16.1 billion per year on average in 2023-24 (2025 data are not yet available). This estimate covers bilateral and multilateral Official Development Assistance (ODA) and non-concessional flows collated in OECD’s Creditor Reporting System (CRS), complemented with Total Official Support for Sustainable Development (TOSSD). It represents only the public component of international finance, rather than total international financial resources for biodiversity (Box 1). International private flows are discussed in sections 2.4, 2.5 and 2.6 below.

The estimate includes 100% of finance associated with activities where biodiversity is a “principal” objective and 40% of finance associated with activities where biodiversity is a “significant” objective (see Table 2 and Annex A for definitions and a detailed description of the methodology). The 40% coefficient is applied because the Rio marker3 data apply to the entire activity reported by the provider rather than solely the finance associated with the biodiversity-specific component. As a result, attributing 100% of significant flows would generally overestimate biodiversity finance. The 40% coefficient is consistent with previous OECD analyses and reflects the most commonly used reporting practice among development providers. Attributing 100% of both principal and significant flows yields an estimate of all biodiversity-related international public finance of USD 29.5 billion per year. This has not been included as an upper range estimate to avoid over-attribution of expenditure to biodiversity and in alignment with delivery practices of countries.

Box 1. Total international finance for biodiversity (public and private) reached USD 18.9 billion in 2024

Total biodiversity-related international financial resources, aggregating both public sources and private, reached USD 18.9 billion in 2024, as reported in “Biodiversity and development finance 2015-2024”. This estimate, which is also based on the OECD Creditor Reporting System and the Total Official Support for Sustainable Development (TOSSD) databases, includes international public finance, private finance mobilised by official development finance and philanthropic funding. Consistent with OECD biodiversity-related development finance methodologies, the estimate attributes 100% of finance associated with activities for which biodiversity is a principal objective and 40% of finance associated with activities for which biodiversity is a significant objective.

Source: (OECD, 2026[6]), Biodiversity and development finance 2015-2024, https://one.oecd.org/document/DCD/DAC/ENV(2026)18/en/pdf

2.4. Private finance for biodiversity

2.4.1. Total flows of private finance for biodiversity

Private biodiversity finance is estimated at USD 12.9 billion per year on average over 2023-25. This estimate covers private investment seeking both biodiversity benefits and financial returns, as well as other private finance, including philanthropic funding and private revenues and other private financial resources received by biodiversity-focused NGOs. The estimate draws on multiple data sources and takes a conservative approach to reduce potential overlaps between them, thereby minimising the risk of double counting.

The private investment component accounted for an estimated USD 9.8 billion on average for 2023-25, with annual investment exceeding USD 14 billion in 2025 (Bennett et al., 2026[7]). This component comprises investments expected to generate positive impacts on biodiversity alongside financial returns. It excludes grants, philanthropy, public environmental funds, and broader environmental, social and governance (ESG) investments or climate investments without a direct and verifiable nature objective.

Other private biodiversity finance is estimated at USD 3.1 billion per year on average over 2023-25. This comprises approximately USD 0.5 billion in international philanthropic finance, USD 0.03 billion in domestic financing from philanthropic organisations, and around USD 2.6 billion in private revenues and other private financial resources received by eight large biodiversity-focused NGOs, after an adjustment for potential double counting with philanthropic finance.

The NGO component is conservative. The analysis identified approximately USD 3.1 billion per year in private financial resources received by eight NGOs. The full value of international and domestic philanthropy identified in separate data sets was deducted from this amount (i.e. approximately USD 0.5 billion), to avoid double counting risk, resulting in an estimate of around USD 2.6 billion per year. This adjustment assumes that all philanthropic finance identified separately is already captured within the private revenues of these eight NGOs. In practice, only part of these flows may overlap, meaning that the resulting estimate may understate the total level of private biodiversity finance. As the eight NGOs were selected based on their overarching focus on addressing biodiversity loss, their eligible private financial resources were counted in full rather than applying a biodiversity-attribution coefficient.

Additional private finance indicators, including private finance mobilised through official development finance are presented in section 2.6. They are not integrated here due to risk of double counting.

2.5. Trends in biodiversity finance

The estimates in this paper are not directly comparable with the estimates presented in OECD’s 2020 analysis, which were based on 2015-17 data (OECD, 2020[3]). Differences in the availability, coverage and methodologies of underlying country data mean that changes in the aggregate estimates cannot be interpreted as changes in global biodiversity finance over time. For example, the methodologies adopted to assess and report public domestic expenditure are not necessarily consistent within countries between 2015-17 and 2023-25, which can affect the scope of expenditure captured. The absence of data for 2023-25 for some major economies, such as India and the United States, further affects comparability. Similar limitations apply to private finance estimates, which continue to rely heavily on one-off studies that have not been repeated for the current reference period. As a result, differences between the OECD (2020[3]) and current estimates primarily reflect changes in data availability, coverage and reporting methodologies rather than underlying changes in biodiversity finance levels.

Assessing trends in biodiversity finance remains challenging owing to limited consistent time-series data and lack of standardised reporting. Nevertheless, several datasets allow (near) like-for-like comparisons for selected finance flows. Together, these indicate a positive trend in biodiversity finance in recent years, both public and private. All data below are based on average annual values expressed in constant 2024 prices.

2.5.1. Trends in public domestic finance for biodiversity

Public domestic expenditure on biodiversity increased by 16% in real terms between 2018-20 and 2023-24 across a sample of 63 countries with consistent and comparable data over time.4 Of these countries, 65% recorded real-term increases in biodiversity expenditure, while the remainder experienced declines. These trends are based exclusively on GFS-COFOG data on 05.4 biodiversity and landscape protection, which provides the broadest coverage across the two periods and applies a consistent functional classification, thereby ensuring comparability over time.

2.5.2. Trends in public international finance for biodiversity

International public finance for biodiversity has increased over this decade, although growth varied across providers. OECD data show that international public finance for biodiversity increased 94% overall between 2018-20 and 2023-24, when counting 100% of principal flows and 40% of significant flows. Finance for activities where biodiversity is a principal objective increased from an average of USD 3.9 billion per year in 2018-20 to USD 7.2 billion in 2023-24, a rise of 85%. Growth was driven primarily by multilateral institutions, while bilateral finance with biodiversity as a principal objective also increased. Finance with biodiversity as a significant objective grew even more strongly, rising by 73% among bilateral providers and by 137% among multilateral providers, more than doubling overall. For an in-depth overview of trends in biodiversity-related development finance, see (OECD, 2026[6]).

2.5.3. Trends in private finance for biodiversity

Identifying trends in overall private finance remains challenging owing to data inconsistencies, differences in methodologies and data gaps. Nevertheless, available data suggests an overall upward trend. For example, average annual private investment in biodiversity reported in Bennett et al. (2026[7]), increased 73% in real terms between the periods 2018-20 and 2023-25. Other indicators show mixed but mainly positive trends. Biodiversity-related private philanthropic flows reported to the OECD Creditor Reporting System declined overall for this period: flows for activities with biodiversity as a significant objective increased slightly, but this rise was more than offset by a decline in flows for activities with biodiversity as a principal objective. By contrast, private finance mobilised by official development finance interventions increased substantially, rising from an annual average of USD 0.2 billion in 2018-20 to USD 1.6 billion in 2023-24 when counting 100% of flows for activities with biodiversity as a principal objective and 40% of flows for activities with biodiversity as a significant objective.

2.6. Complementary information on finance through markets and instruments

In addition to the aggregate estimate of private biodiversity finance, complementary datasets provide insights into broader biodiversity-related financial activity. These include information on corporate expenditures, capital market instruments, mobilised private finance and transactions in environmental markets. These estimates differ in what they measure, geographic and temporal coverage, and their relationship to biodiversity outcomes. Some may also overlap with the aggregate estimate or with one another. They are therefore presented separately and should be neither directly compared nor aggregated into the estimates of global biodiversity finance tracked in this paper (Table 1). Although indicators such as assets under management and biodiversity-related voluntary carbon market transactions are not directly comparable with expenditure, they are included in the complementary information because they provide evidence of the emergence, scale and development of biodiversity-related financial markets and financing channels.

Table 1. Complementary information on biodiversity finance through markets and financial instruments

Market/instrument	Estimate	Year; coverage	What is measured	Caveats or clarifications
Private finance mobilised by official development finance	USD 1.6 billion annually – mobilised finance flow	2023-24 annual average commitments; international	Private finance mobilised through bilateral and multilateral development finance interventions targeting biodiversity	Private finance mobilise by official development finance is included in the estimate of total international development finance.
Domestic corporate expenditure	>USD 7 billion annually – expenditure	2023; 25 countries across EU and OECD	Direct corporate expenditure classified as protection of biodiversity and landscapes (CEP 0502)	Includes businesses whose principal activity is the production of environmental protection services or products and other businesses that carry out biodiversity protection as secondary or ancillary activities
Biodiversity bonds	Corporate: USD 4.1 billion; sovereign USD 15.9 billion; supranational: USD 5.4 billion – bond issuance	2023; global	Green and sustainable bond issuance for which biodiversity is listed among eligible uses of proceeds	From an accounting and reporting perspective, sovereign and supranational bond proceeds are generally classified as public finance. Corporate bonds are generally classified as private finance.
Biodiversity investment funds	USD 1.6 billion – assets under management	September 2024; 24 funds	AUM of 24 “pure-play” funds identified by MSCI as including biodiversity in both their name and investment strategy	AUM is a stock, not an annual finance flow, and does not measure finance reaching biodiversity activities. Strategies vary and may focus on managing biodiversity-related risks rather than financing biodiversity-positive activities
Voluntary biodiversity credits	USD 2.9 million (annual); USD 6 million (cumulative) – tracked transaction value	2025 annual and 2022-25 for cumulative; global	Transactions in the emerging voluntary biodiversity-credit market, excluding credits used for offsetting	The market is nascent and transaction data may be incomplete
Water-quality trading	Over USD 21 million – transaction value	2023; water quality trading programmes involving nature-based solutions	Transactions in credits generated through activities that reduce pollutant loads or improve water quality	Water quality, rather than biodiversity, is the primary objective
Biodiversity-relevant voluntary carbon market projects	USD 488-540 million – estimated value of retired credits	2023-24 average; global voluntary carbon market	Estimated value of retired carbon credits from project categories with strong indication of biodiversity relevance, using retirement volumes and annual average carbon credit prices	An analytical estimate rather than observed expenditure on biodiversity. Biodiversity relevance is inferred from project type or certification and does not indicate the share of proceeds directed to biodiversity or the biodiversity outcomes achieved

Note: OECD (2020[3]) also drew on data on private sector payments for watershed services (i.e. PES), based on data available at the time in Bennett and Ruef (2016[8]). Similarly comprehensive, yet up-to-date data on private sector payments for ecosystem services could not be identified at this time and are therefore not included as a separate category in this table. However, Bennet et al. (2026[7]) do include PES in their analysis on private investment, which is reflected in the aggregate estimate in this paper.

Source: OECD analysis based on various sources. Methodologies and data sources outlined in Annex A.

Notes

← 1.  Global GDP is defined as the sum of the GDP of all United Nations Member States, based on World Bank data. The United States, which was included in the OECD (2020) estimate but is not covered in the present analysis, accounts for approximately 26% of global GDP.

← 2.  This does not include finance reported by the European Union. With EU data added, the range becomes approximately USD 92-165 billion for public domestic expenditure.

← 3.  The OECD-DAC Biodiversity Rio Marker is a policy marker used to identify and track development finance activities that support the objectives of the Convention on Biological Diversity.

← 4.  On average, expenditure also increased by 16% at the individual country level.