Call the bank or credit card company you used to pay the IRS. You can find the number for the bank or credit card company on your monthly statements or on the back of your credit card.
Ask the customer service representative if the check or credit card transaction to the IRS has posted to your account. If you paid by check, you should provide the representative with the check number. If you paid by credit card, you should have the date of the transaction and the amount of the payment to the IRS.
Call the IRS at 800-829-1040. The IRS can provide updated information about your account, including the date the payment was received and if the payment was posted to your account. Even if you verify with your bank or credit card company that the check or credit card transaction cleared, it is a good idea to contact the IRS to confirm that the payment was properly posted to your account.