If you have a ballot paper which you haven't got around to filling in yet - or you have done the voting but haven't posted it yet - then you might want to consider taking your postal vote along to a polling station instead, just to be on the safe side.
Of course, if you post your vote back to the council today (or even tomorrow) it should make it there on time. But if you want to be absolutely certain it doesn't get delayed in the post then you can take it to a polling station on polling day (Thursday!). You still need to complete the ballot paper in the same way as you would if you were posting it, including the declaration.
Just two more days to go before the big day - polls will be open from 7am until 10pm this Thursday (May 6th), so you have 15 hours to take a few minutes to vote. Whether that's handing in a postal vote or getting your ballot papers at the polling station on the day, you will get two ballot papers in Haringey - one for the general election (choose one candidate) and one for the local elections (choose three candidates). Enjoy.