People in England and Wales have until midnight to register to vote in council and mayoral elections on 4 May.
Elections will be held in 34 councils in England and all 22 councils in Wales, and six new regional mayors are being voted in.
A Parliamentary by-election will also take place in the Manchester Gorton constituency.
Elections are also taking place in Scotland, where the registration deadline is midnight on Monday.
People can register to vote online at www.gov.uk/register-to-vote.
Alternatively, paper forms can be downloaded or collected from local registration offices and need to be completed and handed in before the offices close to beat the deadline for England and Wales.
Emma Hartley, of the Electoral Commission, said: "It's important that anyone who is eligible to vote has the opportunity to participate in elections which will have a direct effect on local issues."