Overall AUM increased by 2 per cent from the end of June this year to reach £21.5bn.
In a trading update, the investment group revealed its fiduciary management assets were down 0.3 per cent in the period, “demonstrating our ability to defend and protect client assets in volatile markets”.
It saw net inflows of £592m in the period, while net sales were £152m.
The investment business announced it has been appointed a £1bn mandate from a large UK defined benefit pension scheme, with the structured equity options mandate designed and executed throughout October.
Mike Faulkner, chief executive of River and Mercantile, said: “The difficult market conditions have shown the robustness of the business, both in terms of diversification across asset classes and to continue generating positive flows.
“Our appointment for a large structured equity mandate continues the trend for investors to seek innovative ways to preserve value, while still remaining exposed to risk markets.”
He added its new Global High Alpha equity proposition has been “reviewed by a range of investors”, with inflows expected in the coming months.