A 2ft 4in x 18in (71 x 45cm) interior view of a woman standing in a doorway, dated 1890, overshot its £1500-2000 estimate to contribute £30,000 to the 650-lot sale in Stansted Mountfitchet on March 13.
The oil had come to Sworders via a valuation day in Hertford. The Welsh-born Belleroche was a close friend and studio mate of John Singer Sargent (1856-1925) and, like him, made a name depicting women.
According to the Art Sales Index, the previous record stood at £10,500 for a painting depicting the daughters of minor American painter Edward Boit (a subject Sargent also painted), which sold at Bonhams Knightsbridge in 2008.