Endowment / Foundation

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Social Investment Business

Social Investment Business was founded in 2002 to address the capital gap facing UK charities and social enterprises. Under CEO Nick Temple, it operates as an...

Social Investment Business logo

Social Investment Business

Social Investment Business was founded in 2002 to address the capital gap facing UK charities and social enterprises. Under CEO Nick Temple, it operates as an asset owner using its own balance sheet to provide loan finance, while the Board is chaired by Sonali Siriwardena, a partner at Simmons & Simmons. The foundation traces its roots to early government and civil society partnerships aimed at building a resilient social economy. The foundation blends direct lending, grants, and development programmes across the UK. Its capital supports early-stage, start-up, and expansion-stage ventures in community ownership, affordable housing, and energy resilience. The loan portfolio is supplemented by funds like the Communitybuilders Fund and structured partnerships with Better Society Capital and Access – The Foundation for Social Investment on vehicles such as the Reach Fund and Energy Resilience Fund. Delivery of government-guaranteed loan schemes has been executed alongside the British Business Bank. Since inception, Social Investment Business has channelled over £800 million into thousands of organizations, making it one of the country's largest social investors. Its registered office sits at CAN Mezzanine on Great Dover Street, London, and it also operates the CAN Mezzanine and Canopi commercial workspaces. Beyond balance-sheet finance, the foundation hosts the Social Investment Forum and co-founded the Diversity Forum, embedding itself in sector governance networks like ACF and NCVO, while Siriwardena links the organization to the Global Alliance of Impact Lawyers. Structurally, Social Investment Business is distinguished by its hybrid model: it is a foundation that operates a revolving loan fund rather than perpetually granting. Income from interest and loan repayments is retained and redeployed, creating a permanent capital pool for the UK social sector that sits outside traditional charitable spend-down or pure equity venture models.

General information

Firm type

Endowment / Foundation

Year founded

2002

Location

Region

Europe

Country

United Kingdom

City

London

Corporate office

London, England, United Kingdom

Principals

Nick Temple

Chief Executive Officer

Sonali Siriwardena

Chair of the Board of Trustees

Rt Hon Hazel Blears

Former Chair of the Board of Trustees

Sector focus

Social EnterpriseCommunity DevelopmentAffordable HousingEnergy Transition & Renewables

Frequently asked questions

Is Social Investment Business a grant-making foundation or a lender?

It is primarily a lender using its own balance sheet. While it does provide some grants, its dominant model is providing loan finance to charities and social enterprises. Repaid capital is recycled into new loans rather than being spent down, functioning as a permanent revolving fund.

How does Social Investment Business fund its loan book?

The foundation deploys capital from its own endowment and accumulated reserves. It also partners with co-investors such as Better Society Capital and Access – The Foundation for Social Investment to capitalize specific funds like the Energy Resilience Fund. Additionally, it has acted as a delivery partner for government-guaranteed loan schemes backed by the British Business Bank.

What is the relationship between Social Investment Business and the British Business Bank?

The British Business Bank is a government-owned economic development bank that has partnered with Social Investment Business. Specifically, Social Investment Business acted as an accredited delivery partner for schemes such as the Coronavirus Business Interruption Loan Scheme (CBILS) and the Recovery Loan Scheme (RLS), allowing it to distribute government-backed loans to UK social enterprises.

Who chairs the investment committee or board of Social Investment Business?

Sonali Siriwardena serves as the Chair of the Board of Trustees. She is concurrently a Partner and Global Head of ESG at the international law firm Simmons & Simmons. The foundation is operationally led by Chief Executive Officer Nick Temple.

Does Social Investment Business only operate in London?

No, despite being headquartered in London, the foundation works with charities and social enterprises across the entire United Kingdom. Its community ownership, energy resilience, and social enterprise investments target organizations operating in various regions throughout the UK.

How is the Diversity Forum related to Social Investment Business?

The Diversity Forum is a UK network focused on embedding diversity, equity, and inclusion across the social investment sector. Social Investment Business is a founding partner of the forum and provides organizational hosting support, integrating the network closely with its own governance and sector-development activities.

What investment stages does Social Investment Business typically cover?

The foundation's strategy covers a broad range of maturities. It provides patient capital aimed at early-stage seed and start-up ventures helping communities get projects off the ground. It also supports expansion and late-stage financing for established social enterprises that are ready to grow their impact.

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