FUM were £22.8bn at end December compared to £25bn three months earlier.
The FTSE 100 index dropped by 10.4% over the same period and Charles Stanley said every service type was affected.
New money was steady with discretionary services £0.2bn higher while execution-only funds were flat excluding market movements.
Revenues rose by 0.3% as Charles Stanley Direct grew strongly.
Shares fell 5% to 254p.