Final answer:
An outstanding deposit made on the last day of the month will be added to the bank statement balance in a bank reconciliation.
Step-by-step explanation:
When a bank deposit of $250 made on the last day of the month does not appear on the current month's bank statement, it is treated as an outstanding deposit on the bank reconciliation. The item will be added to the bank statement balance since the deposit was made but not yet reflected on the statement. This adjustment will increase the bank statement balance to match the cash balance in the company's records.