If you didn't receive a rejection notice, your extension is in effect.
If you mailed Form 4868 by April 15th, it is automatically granted. You do not need to wait for an approval letter.
If you sent a payment with your Form 4868, check if the check has been cashed or the funds withdrawn.
The IRS generally does not send confirmation for mailed Form 4868 extensions; it only contacts you if the extension is denied
If you are still concerned, call the IRS at 800-829-1040. You will need your Social Security number and information from your extension form.
