Partygoers were found hiding in cupboards to avoid police when officers raided an organised event which had been booked online.
Fifteen people were issued with fines at the address in Alderley Edge, where police also found balloons and alcohol.
Cheshire Police revealed Saturday night’s raid alongside details of 685 fines issued since the latest lockdown began.
The force said a minority were “blatantly breaching restrictions”.
A spokesman added 116 on-the-spot fines were handed out in one weekend for similar offences.
Parties and gatherings of people in Warrington, Crewe and Widnes were also broken up last weekend, the force said.
Assistant Ch Con Jenny Sims said: “Officers are risking their own health to protect Cheshire residents from this deadly virus and when they are met by blatant and repeat breaches they will enforce without delay.”