Credit balance on suppliers statement

Options
Hello again!

I've just started working for a new company and recently received a monthly statement from one of our suppliers. On this statement there is a credit balance of £525.00 When I queried this with the supplier, due to the age of the credit balance (It goes back 18 months!) they couldn't explain why, apart from that it's a credit on our account. I quick reconciliation my end and I still can't get to the bottom of it!!

What would be the correct treatment in order to "claim" the credit of £525.00? Would it simply be a case of raising an internal credit note and then deducting this from the next invoice(s) due for payment, thus using up the credit balance? Should I request the supplier to raise a credit note ?

Many thanks in advance for any advice.
Privacy Policy