You can e-pay by credit card. If you e-pay by credit card, you delay out-of-pocket expenses and may earn miles, rewards or money back from you credit card issuer. Payment by check or money order is acceptable. If you do owe money, ______________________ will provide you with a voucher and addressed enveloped to mail your check into the IRS. Your return can be e-filed at any time before April 15, and then you can mail your payment in later – as long as it is postmarked on or by April 15.