Energy supplier - date of birth

PlumbingTheDepths

Quick update on this. When I did contact the supplier, Sainsbury's, the first thing they asked for was my name and date of birth. I said that I'd rather not provide it, they said "fine, we can use other things for security".

I've set up to pay by direct debit, but they did say that if I wanted to pay on receipt of bill, I would need to be credit checked, and that they would then need my DOB.