What items do you need to add and what items do you need to subtract when reconciling a checking account bank statement?

You need to include and add up any unposted deposits. If the account is interest-bearing, you add the interest to the net balance.

You then subtract all paid checks, fees/fines, check charges, check purchases (to obtain checks), etc. Lastly, any unposted checks need to be subtracted to reconcile with your personal check ledger.