Family office: definition, single- vs. multi-family offices & how family offices invest

What is a family office?

At its core, a family office exists to solve a coordination problem. As family wealth grows and spreads across asset classes, entities, and generations, using outside advisors piecemeal becomes inefficient and risks conflicting advice. A family office consolidates that decision-making with dedicated, full-time staff whose only client is the family (or families) they serve.

Example: A founder who sells a company for $400 million might set up a family office with a CIO, a controller, and a small investment team. That team then manages public and private portfolio allocations, coordinates with outside tax counsel, and administers philanthropic giving — all under one roof, reporting only to the family.

Single-family office vs. multi-family office

• Single-family office (SFO): Serves one family exclusively. Common among families with several hundred million dollars or more in assets, given the fixed costs of running a dedicated team of investment, tax, and legal professionals.
• Multi-family office (MFO): Serves several unrelated families, sharing staff and infrastructure to lower costs. This is a more accessible entry point for families with meaningful but smaller capital, often starting in the tens of millions rather than hundreds of millions.

How family offices invest

Family offices are known for long time horizons and a willingness to hold illiquid positions, which makes them active participants in private equity, venture capital, real estate, and direct deals alongside more traditional public-market allocations. Because a family office is not managing outside investor capital with a fixed fund life, it can hold an investment for a decade or more if that fits the family’s goals.

Many family offices also build direct relationships with fund managers to access co-investment opportunities and improve deal flow, effectively behaving like a small institutional investor even though the capital belongs to one family. This is part of why family offices are frequently found on the cap tables of pre-IPO companies and growth-stage private deals.

Final thoughts

A family office is less a product and more an operating model: dedicated staff, singular loyalty, and a mandate built around one family’s full financial picture rather than a fund’s return target. The bigger the balance sheet and the more complex the goals, the more that model tends to pay for itself.

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