A £25,000 prize is up for grabs to anyone paying their council tax by Direct Debit.
For the chance to win, residents must register to make payments under the system by July 15.
All those already paying by Direct Debit will automatically be entered into the prize draw.
Hounslow is one of 20 boroughs participating in the scheme, in conjunction with Bacs, the company responsible for Direct Debit.
To switch your payments to Direct Debit, you can return a completed paper Direct Debit instruction to the council, sign up at www.hounslow.gov.uk or call 020 8583 4242.