How to fax a form to the IRS
The IRS accepts some forms by fax, including Form SS-4 (to get an EIN) and Forms 2848 and 8821 (sent to the CAF unit). Find the fax number in the form’s instructions or on your IRS notice, then send the pages online.
Check first: Tax returns such as Form 1040 are filed electronically or by mail, not by fax, unless an IRS notice asks you to fax something.
How to send it
- Check the form’s instructions on irs.gov (for SS-4, 2848 or 8821) or your IRS notice for the fax number. The IRS lists different numbers by form and by state.
- Sign the form. Form 2848 sent by fax needs a handwritten signature, not a typed one.
- Scan or upload the signed pages and add a cover page with your name, the form number and a phone number.
- Send it with ConfirmFax and keep the delivery receipt with your tax records.
Tips so it isn’t rejected
- Form SS-4 by fax (Fax-TIN): the IRS faxes your EIN back, usually within about four business days, so include a fax number where you can receive it, or use the free online EIN application instead.
- Form 2848 and 8821 can also be uploaded at IRS.gov/Submit2848, which is free if you have an account.
- Write your name and the last four digits of your SSN or EIN on every page in case pages get separated.
- Use the fax number printed on your form, notice or letter. Agencies use different numbers for different forms and regions.
Official guidance: IRS: Instructions for Form SS-4 · IRS: Instructions for Form 2848. Fax numbers change; always use the number printed on your form or letter. Last checked November 2026.
Questions
Can I fax my tax return to the IRS?
Generally no. Returns are e-filed or mailed. Only fax a return or document if an IRS notice or IRS employee gives you a fax number for it.
How do I get my EIN back if I don’t have a fax machine?
Either apply online at irs.gov (fastest, free) or get your own ConfirmFax number to receive the IRS reply. The IRS faxes the EIN to the number you put on Form SS-4.