Family office staffing by size: headcount at $250m to $5bn

A family office with $250m of assets typically employs two to six people, one with $1bn employs around ten to twenty, and only the largest offices pass fifty. The averages in the benchmark reports run higher than the medians because a small number of very large offices pull them up. Roughly 40% of staff are in non-investment roles, and the number depends as much on what the office does for the family as on the size of the portfolio.

The headline numbers

Morgan Stanley's 2025 Single Family Office Compensation Report, based on 433 firms, found an average of 19.5 in-house staff, 29.8 at offices with $1bn or more and 8.5 below. The same offices supported on average 10.2 households, 27.4 family members and 2.8 generations, with a ratio of 1.4 family members per staff member.

J.P. Morgan's 2024 Global Family Office Report, as summarised by Caproasia, is the only source to publish medians alongside averages, and the gap is large: an average of 19.7 at offices over $1bn against a median of 9.1, and 6.1 against 2.1 below $500m. Half of all offices in that survey had five employees or fewer, 22% had six to ten, 17% had eleven to twenty and 3% had more than fifty.

UBS's Global Family Office Report 2025 found an average of 12 employees across 317 offices with average assets of $1.1bn, noting that 6% of US offices and 5% of Southeast Asian offices employ more than fifty. The KPMG and Agreus 2025 Global Family Office Compensation Benchmark Report found the most common team size was fewer than five employees, at 38% of respondents. Deloitte's 2024 trends report put the average at 15 staff for offices averaging $2.0bn.

Reading the bands

Putting the sources together gives approximate ranges rather than a formula.

A $250m office sits in J.P. Morgan's lowest band, where the median was 2.1 and the average 6.1. Heidrick & Struggles' 2025 survey found most investment teams number five people or fewer even at larger offices, so at this size the investment function is usually one or two people plus an outsourced CIO or external managers. The trade-off is set out in outsourced CIO versus in-house.

A $1bn office sits at the boundary of every survey's top band. J.P. Morgan's median of 9.1 and Morgan Stanley's sub-$1bn average of 8.5 bracket it at around eight to ten people, typically a CEO or CIO, a CFO or controller, two to four investment staff and two to four in accounting, administration and family services.

For a $5bn office the surveys offer no separate band. Morgan Stanley's $1bn-plus average of 29.8 and UBS's finding that only 5% to 6% of offices in the largest markets exceed fifty staff suggest a range of twenty-five to fifty, with the higher figure where the office runs direct investments, multiple branches or household services. Deloitte's 2024 landscape report found 28% of offices have multiple branches, which adds headcount independent of assets.

What drives the number beyond assets

The split between investment and non-investment staff is the first driver. UBS's 2026 report found non-investment professionals in operations, accounting, legal support and lifestyle services make up 40% of total staff. Morgan Stanley's 2025 data shows investment-focused offices run leaner (17.5 staff on average) and support fewer entities (72.9 against 100.7 for all offices).

The second is the investment model. Morgan Stanley's 2025 report found 56% of investment-focused offices manage investments directly in house; a direct investment team needs associates and analysts that an allocator does not. The third is outsourcing. J.P. Morgan's 2024 data shows legal services are outsourced by 81% of offices, cybersecurity by 59%, accounting and tax by 54% and estate planning by 57%, while financial administration (88%) and staffing and compensation (87%) are kept in house.

Growth and cost

Teams are growing slowly. The KPMG and Agreus 2025 report found 35% of offices grew their team in the year, 57% held it flat and 8% reduced it. Deloitte's 2024 report found four in ten offices planned to hire. Each hire is expensive relative to assets at the small end: the AlTi and Campden 2025 Family Office Operational Excellence Report found C-suite pay is 72% of total costs at offices under $250m against 39% above $1bn. Cost benchmarks are in family office operating costs.

Closing

Medians are the better guide for a new office; averages describe what the field looks like once the largest families are included. A $250m office that plans for three to five people, a $1bn office for eight to twelve and a $5bn office for thirty or more will be within the range the surveys describe.