LEWES District Council is urging people to register to vote by Thursday April 14.
There are district, town and parish council elections taking place on May 5.
Voters can also take part in the first UK wide referendum in over 30 years which will be held on the same day.
The referendum is on the voting system used for elections to the UK Parliament.
The question being put to voters on May 5 is: “At present, the UK uses the ’first past the post’ system to elect MPs to the House of Commons. Should the ’alternative vote’ system be used instead?”
The Electoral Commission, the independent elections watchdog, is sending a booklet to every household in the UK with information about how to have your say.
For those who are unable to vote on the day, they can now apply to vote by post or by proxy.
The council’s returning officer said: “Now is the time to make sure you are registered to vote before the deadline on Thursday April 14 and to apply for a postal or proxy vote.
“The process is easy and only takes a few minutes.”
Electoral Commission regional manager Phillippa Saray said: “People don’t always realise that they can have their say in different ways, including by post of by asking someone you trust (a ‘proxy’) to cast your vote for you.
“So if you are going to be away on Thursday 5 May, take a few minutes now to make sure your voice will still be heard.”
To request the forms contact 01273 484116.