There are several ways.
You can get Form 4868 from the IRS at www.irs.gov now.
You don’t need to file Form 4868 if you make a payment using the IRS electronic payment options.
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You can pay all or part of your estimated income tax due and **indicate that the payment is for an extension** using Direct Pay, the Electronic Federal Tax Payment System, or using a credit or debit card. Your extension is then automatically granted and you will receive a confirmation number for your records.
If you e-file Form 4868 and mail a check or money order to
the IRS for payment, use a completed paper Form 4868 as a
voucher. Please note with your payment that your extension request was originally filed electronically.
