Over the past five years, the stock of ESG debt securities has quadrupled in Portugal and in the euro area.
Source: Banco de Portugal and European Central Bank
In Portugal, the amount of ESG debt securities issued has quadrupled over the past five years. In December 2020, they accounted for 1.0% of the total securities issued by residents, amounting to €3.3 billion. In December 2025, they reached €13.6 billion, representing 4.3% of the total. Despite this increase, the weight of ESG securities in the domestic market remains low. Since mid‑2024, their share has stabilized at around 4%.
In the euro area, the trend was similar: ESG debt securities also nearly quadrupled over the five‑year period. In December 2020, they totaled €462 billion (2.3% of the total), and by December 2025 they had reached €1,835 billion (7.1% of the total). The slowdown in these issuances occurred later than in Portugal, only in 2025.
Source: Banco de Portugal and European Central Bank
Between the end of 2020 and the end of 2025, most countries recorded an increase in the share of ESG securities in their total stock of debt securities. The rise was more pronounced - above 8 percentage points - in the Netherlands, Slovenia and Cyprus. In December 2025, the Netherlands ranked first among euro area countries in terms of the relative weight of ESG securities, with 12.4% of total securities issued.
Which categories are most relevant in ESG financing?
Source: Banco de Portugal
In Portugal, debt securities issued to finance environmental (‘green’) projects predominate. In December 2025, this category accounted for 68% of the €13.6 billion in ESG debt securities issued by resident entities. The ‘sustainability‑linked’ category, which finances projects without a specific allocation but with future ESG commitments, has gained relevance in recent years, representing 21% of the total at the end of 2025. Debt securities intended to finance social projects accounted for only 8%.
Source: Banco de Portugal and European Central Bank
In the euro area, the dominant category is also the ‘green’ segment, accounting for 66% in December 2025, within a total stock of €1,835 billion. The ‘sustainability‑linked’ category had a lower weight than in Portugal (9%). By contrast, ESG debt securities issued to finance projects with a positive social impact had greater relevance (17%).
Source: Banco de Portugal and European Central Bank
In most countries, the ‘green’ category was predominant.
Quem se financia através de títulos ESG?
Source: Banco de Portugal
In Portugal, most ESG debt securities issuances finance the non‑financial corporations sector (74% at the end of 2025). The weight of the financial sector in issuances has increased, rising from 12% in December 2020 to 26% at the end of 2025. The general government has not yet issued ESG debt securities.
Source: Banco de Portugal and European Central Bank
In the euro area, the distribution is different. At the end of the year, non‑financial corporations accounted for 22% of total ESG issuances, the financial sector for 43% and the general government for 35%.
Source: Banco de Portugal and European Central Bank
The difference across countries is significant. France stood out due to the predominance of general government issuances (57% of the total stock of €569 billion). Germany and the Netherlands recorded a higher weight of the financial sector (52% and 71%, respectively, of total stocks of €372 billion and €312 billion). Portugal stood out for the predominance of non‑financial corporations.
And who invests in the ESG securities issued in Portugal?
Source: Banco de Portugal
Most ESG securities issued by residents in Portugal are held by non‑residents: 67%, according to the latest available data for September 2025.
Most ESG securities issued by residents in Portugal are held by non‑residents: 67%, according to the latest available data for September 2025.
Source: Banco de Portugal and European Central Bank
In terms of the geographical distribution of investors, in addition to Portugal (33%), holdings were mainly concentrated in Luxembourg (14%), the United States of America (9%), France (8%), Spain (7%) and the United Kingdom (7%).
Which ESG categories do resident investors invest in?
Source: Banco de Portugal
Resident investors in Portugal invested mainly in environmental projects: ‘green’ bonds accounted for 58% of the €16.4 billion invested in ESG debt securities in September 2025. However, between 2021 and 2025, this category lost relevance, in contrast with the ‘sustainability‑linked’ category (up by 14 pp) and the ‘social’ category (up by 3 pp). Of the total investment in ESG securities, 27% (€4.5 billion) corresponded to securities issued by resident entities.
Source: Banco de Portugal and European Central Bank
In the euro area, environmental projects also predominate. On the same date, they accounted for 66% of total investment in ESG debt securities (total stock of €1,781 billion). The ‘green’ category was, in fact, the one that grew the most since 2021 (+6 pp). By contrast, the weight of ‘sustainability’ bonds (which combine environmental and social impact) decreased by 3 pp.
Source: Banco de Portugal and European Central Bank
In most euro area countries, the ‘green’ category was the most relevant, with shares above 70% recorded in Lithuania, Estonia, the Netherlands, Italy, Finland and Luxembourg. In the ‘social’ category, Slovakia stood out, with 45% of total investment in ESG debt securities. Portugal was the country where the ‘sustainability‑linked’ category had the highest weight: 21% of total investment in ESG debt securities.
How is this investment distributed by sector?
Source: Banco de Portugal
In Portugal, the financial sector clearly dominates investment in ESG securities. In September 2025, banks accounted for 50% of the total, insurance corporations and pension funds for 31% and other financial institutions for 11%. Banks recorded the largest increase in weight (+15 pp), while the share of insurance corporations and pension funds declined by 16 pp. Households represented only 6% of investment in ESG securities, although their relative importance increased by 5 pp since September 2021.
Source: Banco de Portugal and European Central Bank
In the euro area, the financial sector is also the main investor. Banks and other financial institutions accounted for 36% and 34% of investment in ESG securities in September 2025, respectively, while insurance corporations and pension funds represented 25%.
What is an ESG debt security?
An ESG debt security is a financial instrument that incorporates environmental, social and governance sustainability criteria in its purpose or structure. The ESG classification is assigned based on the specific characteristics of the security and the information disclosed by the issuer.
These instruments are designed to finance projects with sustainability objectives and generally fall into one of four categories:
Green ESG bonds
Green bonds
They finance environmental projects, such as environmental protection, renewable energy, energy efficiency or the sustainable management of natural resources.
Social ESG bonds
Social bonds
They finance projects with a positive social impact, such as affordable housing, social inclusion, support for vulnerable populations, or health and education initiatives.
Sustainability bonds
They finance projects that combine environmental and social objectives, integrating elements of both the ‘green’ and ‘social’ categories.
Sustainability‑linked bonds
In these instruments, the funds raised are not allocated to a specific project, but the issuer commits to meeting future ESG targets (for example, reducing CO₂ emissions). The interest rate may be adjusted depending on whether these targets are met or not.