Braintree Council is offering a £100 prize for residents and businesses who sign up to e-billing.
The e-billing system, available through the council website, allows residents to register and receive their council tax bill via email rather than the post.
Businesses can also register to receive their business rates bill online.
The deadline to sign up and be in with a chance of winning the cash is February 21.
Councillor David Bebb, cabinet member for resources, said: “This is not about the way you pay your bill but rather how you receive the bill itself.
“As with utility companies, many people prefer to receive bills and correspondence online, and via the e-billing system we want to significantly reduce the number of people receiving their bills through the post.
“We currently have over 62,000 live accounts paying council tax and almost 4,500 business rate payers, and a lot of money is being spent each year in posting out the bills to people.”
Registering takes about five minutes and can be done via braintree.gov.uk/e-billing.