At year end, there was a total of 250,000 in sales deposited during the year, but not recorded. What would be my adjusting entry?

What was not recorded - the sales, the deposits, or both?

Both

To record the deposits:

DR Cash in bank 250,000

To record the sales:

CR Sales 250,000


Is there any bank reconciliation being performed every month? Surely, the deposits would appear in the bank statements which did not appear in your books. Tracing back the source transaction would have revealed the unrecorded sales.

I hope this solves your problem.