Answer: Three, if you live in Haringey.
But giving people three votes isn't part of some exciting experiment with proportional representation. It's a cock-up.
Some of the general election ballot papers sent out to postal voters in Hornsey and Wood Green are very clearly marked across the top with VOTE FOR NO MORE THAN THREE CANDIDATES. Whoops. Might be a welcome instruction for indecisive voters, but it isn't going to help us with an accurate election result.
I don't know how many voters are affected yet (my own postal ballot paper correctly told me to vote for just one candidate), but what I do know is that it is already causing confusion. Haringey are aware of the problem, but not sure yet exactly what they are proposing to do.
Just as a reminder, while you do get to mark three crosses on the ballot paper for the local elections, please do make sure you only mark the one cross on any general election ballot paper.
Let's hope this can get sorted and it doesn't cause chaos with the election...