To get a copy of your tax ID number from the IRS, start with your own records, and if the number isn’t there, call the IRS directly: the Business and Specialty Tax Line at 800-829-4933 for an Employer Identification Number, or the individual line at 800-829-1040 for an Individual Taxpayer Identification Number. Both lines will verify your identity and confirm the number by phone, and you can request written proof by mail or fax. One important difference shapes everything that follows: an EIN is permanent, but an ITIN can expire, which means retrieving an old ITIN sometimes turns into renewing it.
Look Here Before Contacting the IRS
The IRS recommends checking a few places before you call. For an EIN:
- The original CP 575 confirmation notice the IRS mailed when it first assigned the number.
- Any federal tax return your business has filed — the EIN appears on every one.
- The bank where you opened your business account, since the institution collected your EIN during setup.
- State or local business license applications, which typically required the EIN.
For an ITIN, the equivalent record is the CP 565 notice the IRS mailed when the number was first assigned or later renewed. Any prior-year federal tax return you kept a copy of will also show the ITIN.
Getting an EIN From the IRS
If nothing in your records turns up the number, the IRS offers two official retrieval methods.
Request an Entity Transcript
An entity transcript is a record of your business’s tax account information and includes your EIN. You can get one three ways:
- Online, by logging into your IRS business tax account to view, print, or download it immediately.
- By phone, through the automated transcript line at 800-908-9946.
- By mail, using Form 4506-T (Request for Transcript of Tax Return), sent to the address listed for your state in the form’s instructions.
Online and phone requests are fastest. A mailed Form 4506-T works when you don’t have online access.
Call the Business and Specialty Tax Line
The most direct route is the IRS Business and Specialty Tax Line at 800-829-4933, open Monday through Friday, 7:00 a.m. to 7:00 p.m. in your local time zone (Alaska and Hawaii follow Pacific time).1Internal Revenue Service. Employer Identification Number Only someone authorized to act for the business can receive the number. For a sole proprietorship, that means the individual owner. For a corporation, it includes the president, vice president, secretary, treasurer, or CEO. For a partnership, any responsible and duly authorized partner qualifies.2Internal Revenue Service. 21.7.13 Assigning Employer Identification Numbers (EINs)
After verifying your identity, the representative reads the EIN to you over the phone. If you need something in writing, ask for Letter 147C, the IRS’s official EIN verification letter. The IRS does not reissue the original CP 575 notice, so Letter 147C is the substitute, and it can be sent by mail or fax.1Internal Revenue Service. Employer Identification Number Banks and state licensing agencies routinely accept it as proof.
An EIN is permanent. Once the IRS assigns one, it stays with that business entity forever. The IRS can deactivate an EIN that’s no longer needed, but the number is never canceled or reassigned to someone else.3Internal Revenue Service. If You No Longer Need Your EIN So if you’re wondering whether an EIN from years ago is still yours, it is.
Getting an ITIN From the IRS
ITIN retrieval runs through different channels than EIN retrieval.
Call the IRS Individual Line
The main toll-free line for individuals is 800-829-1040, open Monday through Friday from 7:00 a.m. to 7:00 p.m. local time. Have your full legal name, date of birth, and any Social Security Number or ITIN you’ve used before ready. The representative uses this information to verify your identity before disclosing anything about your account.4Internal Revenue Service. Let Us Help You If you want written confirmation, ask for a replacement CP 565 notice.5Internal Revenue Service. Notice CP565
Use Your IRS Online Account
ITIN holders can create an IRS online account using ID.me identity verification.6Internal Revenue Service. How to Register for IRS Online Self-Help Tools Once you’re in, you can view your tax records and your ITIN without waiting on hold. The first-time setup requires a photo ID and a selfie through ID.me and takes a few minutes.
Visit a Taxpayer Assistance Center
If you’d rather handle it in person, visit a local Taxpayer Assistance Center. Appointments are required. Call 844-545-5640 first to schedule and confirm that the nearest location handles what you need.4Internal Revenue Service. Let Us Help You Bring a government-issued photo ID and any prior IRS correspondence you have.
Work With a Certifying Acceptance Agent
Certifying Acceptance Agents are authorized by the IRS to help foreign nationals and others who don’t qualify for a Social Security Number obtain or recover an ITIN. They review your identification, complete the paperwork, and forward everything to the IRS on your behalf.7Internal Revenue Service. How to Become an Acceptance Agent for IRS ITIN Numbers This is often the easier path if you’re outside the United States.
If Your ITIN Has Expired
An ITIN expires on December 31 of the third consecutive tax year it isn’t used on a federal return.8Internal Revenue Service. How to Renew an ITIN If the number you’re trying to retrieve has lapsed, you’ll need to renew it before it can be used on a return.
Renewal is done by filing Form W-7 (Application for IRS Individual Taxpayer Identification Number) with the “Renew an existing ITIN” box selected. If you don’t remember the old number, check the “No/Don’t know” box and the IRS will look it up.8Internal Revenue Service. How to Renew an ITIN
You’ll submit documents proving identity and foreign status. A valid passport is the simplest option because it’s the only standalone document the IRS accepts. Anything else — such as a national identification card or birth certificate — must be paired with at least one other document so that the combination covers both identity and foreign status. All documents must be originals or certified copies from the issuing agency. Notarized copies aren’t accepted.9Internal Revenue Service. ITIN Supporting Documents If your legal name has changed since the ITIN was first issued, include a marriage certificate or court order showing the change.
Processing usually takes about seven weeks. Between January 15 and April 30, or when applying from overseas, allow nine to eleven weeks.10Internal Revenue Service. Individual Taxpayer Identification Number (ITIN) When a spouse or dependent renews to be claimed for a tax benefit, the renewed ITIN has to be listed on an attached federal tax return along with the relevant schedule or form.
Having Someone Else Retrieve Your Number
If you’d rather have a CPA, attorney, or enrolled agent handle it, file Form 2848 (Power of Attorney and Declaration of Representative). The form authorizes your representative to access your confidential tax information, which includes retrieving an EIN or ITIN on your behalf. Signatures on mailed or faxed submissions must be handwritten; digital or typed signatures aren’t accepted through those channels.11Internal Revenue Service. Instructions for Form 2848 This is the common route during a business transition, an estate matter, or any situation where the original responsible party is no longer available. Once the authorization is on file, the representative can call the IRS and handle verification without you on the line.
If Someone Else Has Been Using Your Number
Sometimes the reason you’re looking for your tax ID is that someone else has already been using it. A rejected e-file because a return was already submitted under your number, or IRS notices about returns you never filed, points to identity theft, and the process shifts from retrieval to reporting.
For a business EIN, file Form 14039-B (Business Identity Theft Affidavit) with the IRS and include all requested supporting documents. Sign it to avoid processing delays. Also file if you receive a balance-due notice you don’t owe or a notice referencing a business you never formed.12Internal Revenue Service. Report Identity Theft for a Business
For individual ITIN theft, complete Form 14039 (Identity Theft Affidavit) and attach it to the back of a paper tax return, or submit the form and the return separately. Respond promptly to any follow-up IRS requests, but don’t submit duplicate forms or call to check status; that slows the case down.13Internal Revenue Service. How IRS ID Theft Victim Assistance Works
One exception: if you receive a Taxpayer Protection Program letter (5071C, 4883C, or 5747C), don’t file Form 14039. Those letters carry their own verification instructions, typically pointing you to an online verification tool or a dedicated toll-free number, and you should follow the steps in the letter.13Internal Revenue Service. How IRS ID Theft Victim Assistance Works
State Tax IDs Are Separate
State tax IDs are administered separately from your federal EIN or ITIN, so calling the IRS won’t recover one. Most states handle business tax registration through a Department of Revenue or similar agency, and many offer an online business portal where you can view your registration certificate and account details. If the portal doesn’t work for you, contact the state agency directly; processing times for a mailed duplicate notice vary by state.