The Family Office: SFO vs. MFO Blueprints

The Family Office: SFO vs. MFO Blueprints

The $100M question: When to build in-house (SFO) versus outsourcing (MFO), and the “Virtual” middle ground.

Dec 24, 2025 Code Authority: Team BMT STRUCTURE & OPS

Executive Summary

  • The $100M Threshold: Generally, a full Single Family Office (SFO) requires $100M+ in AUM to justify the $1.5M-$2M annual operating overhead (approx. 1-2% cost drag).
  • MFO vs. VFO: For estates under $100M, a Multi-Family Office (MFO) or a Virtual Family Office (VFO) offers institutional access without the HR burden.
  • Control Premium: SFOs provide 100% privacy, customization, and no conflict of interest, but require managing a C-suite team (CIO, CFO, GC).

The “Overhead” Trap

Building an SFO too early (e.g., at $30M AUM) is a wealth destroyer. Fixed costs (staff, tech, rent) can easily exceed 3-4% of assets, eroding returns faster than market alpha can generate them.

Mechanic: Structural Economics

$100M+
SFO Min AUM
$1.5M+
Annual OpEx
VFO
Hybrid Model
Control
SFO Benefit

Simulation: Cost Efficiency ($200M AUM Scenario)

Total Annual Cost: MFO Fees vs. SFO OpEx
MFO Fee (~0.85% AUM)~$1.7M Variable Cost
Costs Rise with Wealth
SFO Budget (Fixed OpEx)~$1.5M Fixed Cost
Economies of Scale
At $200M LevelSFO Wins (Cheaper + Control)
Optimum Structure
Feature Multi-Family (MFO) Single-Family (SFO)
Cost Structure % of AUM (Variable) Fixed Salaries/Ops
Privacy/Control Shared Resources Absolute Control
Ideal Asset Size $10M – $100M $100M – Billion+

“If you have seen one Family Office, you have seen one Family Office. But the laws of math apply to all: Scale determines structure.”

Essential Resources