Form 15101 – Replace ATIN with SSN, Addresses, Fax, CP Notices

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The adoption is finished, the Social Security card finally shows up, and the return keeps bouncing because the IRS still has the old ATIN on file. Form 15101 is the step that closes that gap. It tells the IRS the child now has an SSN so the temporary ATIN can be retired.

It does not request the SSN itself, since only the Social Security Administration issues one, through Form SS-5. File it as soon as the number arrives and stop using the ATIN on returns, since continuing to use it can create processing conflicts. Submit by mail to Stop 6182 in Austin or by fax, and if the address has changed since the ATIN was issued, write the new one in the address section.

Key Takeaways

• Form 15101 tells the IRS that your adopted child now has an SSN and that the temporary ATIN should be retired.
• File as soon as the SSN is issued. From that point forward, stop using the ATIN on your returns, since continuing to use the ATIN after the SSN has been assigned can create IRS processing conflicts.
• Submit by mail to the ATIN Unit at Stop 6182 in Austin, by overnight to the Interregional Highway address, or by fax.
• Use the fax number listed on your CP notice if you choose to fax, or the form’s standing fax number, (855) 250-1731. Keep your proof of transmission.
• If your address has changed since the ATIN was issued, write the new address in the address section on Form 15101.

What Form 15101 Is and Who Should Use It

Form 15101, Provide a Social Security Number (SSN) for Adoptive Child, is how you tell the IRS that your child now has an SSN and that the ATIN on your account should be replaced. The IRS includes Form 15101 with several ATIN notices, and you complete it and return it to the IRS by fax or mail.

Use it if all of the following are true:

• Your child was previously issued an ATIN for tax filing.
• The Social Security Administration has now assigned an SSN for your child.
• You need the IRS to update your records and retire the ATIN.

Important boundary:

• Do not use Form 15101 to request an SSN. Only the Social Security Administration can issue one.

Why timing matters

Filing Form 15101 right after the SSN arrives helps you avoid mismatches, processing delays, and follow up notices. Several IRS CP notices, including CP560 and CP561 series, tell you to complete Form 15101 once you receive an SSN.

Form 15101 vs. W‑7A vs. 15100, Which One Do You Need?

Choosing the right form depends on where you are in the adoption timeline. Here is a quick map.

Form	Use this when	How you submit	Extra notes
W‑7A, Application for ATIN	Adoption is pending and the child has no SSN	Mail to Stop 6182 in Austin, or submit via a TAC that forwards your application	Expect about 4 to 8 weeks for processing. The ATIN phone line is 737‑800‑5511.
15100, ATIN Extension Request	Your ATIN is expiring and you still do not have an SSN	Included with certain CP notices, reply by upload when allowed, or by fax or mail per notice	Used to request a 1‑year extension and to communicate updates noted in the notice.
15101, Provide SSN for Adoptive Child	You now have your child’s SSN and need the IRS to replace the ATIN	Send by mail, overnight, or fax	Do not use to obtain an SSN. Use only after the SSN is assigned.

What-How-Wow in practice

• What: Form 15101 updates the IRS from ATIN to SSN.
• How: Complete parent information, the child’s SSN and name, the old ATIN, sign, and submit per your notice or to the Austin addresses below.
• Wow: If you file promptly, you reduce rework during tax season and protect eligibility for benefits that require an SSN, such as the EITC.

When to File Form 15101 After Your Child Gets an SSN

File immediately. IRS guidance tied to the CP560 and CP561 series explicitly instructs you to complete Form 15101 once you receive the SSN for your child. That way the IRS stops expecting an ATIN on your return and aligns your account with Social Security. Complete the form and return it to the IRS by fax or mail.

If you received a CP561C stating that an ATIN expired, detach and include the stub with your response. This helps the IRS match your SSN update to the right ATIN record.

If you do not have an SSN yet and the adoption is still pending, request an ATIN extension with Form 15100 using the reply options in your notice, rather than filing Form 15101 prematurely.

Complete Form 15101 Step by Step

Before you start, have your child’s Social Security card and any IRS notice stubs handy. If a CP560 or CP561 notice came with a detachable stub, plan to include it with your filing.

Parent and contact details

• Enter up to two adoptive parents’ full names and SSNs.
• Provide your current mailing address.
• Add two phone numbers and your preferred call times, so the ATIN Unit can reach you if needed.

If your address has changed since the ATIN was issued, write your new address in the address section on Form 15101.

Child identification

• Enter the child’s SSN exactly as it appears on the Social Security card.
• Enter the child’s full legal name.
• List the prior ATIN that the IRS issued for your child.

Signatures

• Sign and date where indicated. If two adoptive parents are listed, both should sign (the form calls for original, wet signatures, so typed or electronic signatures are not accepted).

Attachments

• Include the detachable stub from any CP560 or CP561 notice you received. This helps the IRS link your update to the correct account.
• Only include documents your notice specifically asks for. When in doubt, keep it simple and follow the notice checklist.

How to Submit Form 15101

You have three legitimate paths. Choose the one your notice allows and keep proof of submission.

1) Mail

Standard mail address for the ATIN Unit:

• Department of the Treasury, Internal Revenue Service, Stop 6182, Austin, TX 73301‑0066.

Tip: Use USPS with tracking and keep a copy of everything you send.

2) Overnight or private delivery

Use the IRS Austin street address for express couriers:

• Internal Revenue Service, 3651 S. Interregional Highway 35, Stop 6182, Austin, TX 78741.

Ask your carrier for written proof of the mailing date.

3) Fax

If your CP notice lists a fax option, use the fax number shown in your notice and keep the transmission confirmation page with your records. The form itself also prints a standing IRS fax number, (855) 250-1731, that you can use even without a notice. IRS CP pages instruct you to fax to the number in your letter if you prefer that method.

A note on online upload

Form 15101 is a paper form. The IRS instructions direct you to complete it and fax or mail it to the addresses above, so submit it by fax or mail rather than through an online upload tool.

Processing timelines and status checks

If you are applying for, or extending, an ATIN with W‑7A or 15100, plan for about 4 to 8 weeks after the IRS receives a complete package. If it has been at least 8 weeks with no update, call the Austin Service Center at 737‑800‑5511 for ATIN status. This number is not toll‑free.

Once you have an SSN and file Form 15101, the update itself is usually faster than an ATIN application. Keep copies of everything and wait for your next filing to reflect the SSN.

Common Pitfalls and Simple Fixes

Pitfall	Better move	Why it matters
Trying to e-file or upload the form	Submit Form 15101 by fax or mail only	The IRS instructions direct you to fax or mail the completed form; it is a paper or fax submission.
Using 15101 to get an SSN	Apply with the Social Security Administration for the SSN	Only SSA issues SSNs, not the IRS.
Leaving an out-of-date address on the form	Write your new address in the address section on Form 15101	The form instructs you to write a changed address on it, which keeps IRS correspondence from going to the wrong location.
ATIN expired, no SSN yet	Use Form 15100 to request a 1‑year extension per your CP notice	Prevents lapses while the adoption is pending.

For CPA and EA Firms: Keep delivery tight during peak season

If you handle a high volume of adoption‑related filings, build a simple checklist that pairs each ATIN CP notice with the correct next step, the correct address, and the allowed reply method. Tie it to your practice management system so preparers cannot move work to review without attaching the right CP stub or upload confirmation. This protects turnaround and review time when your teams are stretched.

Accountably works with CPA and EA firms that need dependable offshore production without losing workflow control. In practice, that means SOP‑driven workpapers, layered review, clear SLAs, and continuity plans so Form 15101 updates, W‑7A mailings, and 15100 extensions do not get stuck in review loops during peak season. Use this kind of structure whether you run work in‑house or with a partner.

Final Checklist

• SSN issued by SSA, not the IRS.
• Form 15101 completed with parent info, child’s SSN and name, and prior ATIN.
• Any CP560 or CP561 notice stub included, if you received one.
• Submission sent by mail to Stop 6182, overnight to the Interregional Highway address, or by fax to (855) 250-1731.
• Changed address written in the address section on Form 15101.

Compliance note: Addresses, notice instructions, and timelines in this guide were verified against IRS sources as of January 15, 2026. Always follow the instructions on your specific CP notice, especially for the fax and mailing details.

Sources and trust signals

• IRS Adoption Taxpayer Identification Number page for the roles of W‑7A, 15100, and 15101, plus the EITC SSN requirement and the ATIN status line.
• W‑7A instructions and the Internal Revenue Manual for the Austin Stop 6182 and the overnight street address.
• CP560 and CP561 notice pages that instruct taxpayers to use Form 15101 when an SSN is received.
• Form 8822 guidance for official address changes.

Common Mistakes We See Every Season

Most Form 15101 problems trace back to a handful of recurring mix-ups between the form’s reporting job and the separate SSN application step. Here are the ones my team flags most often, with the fix we drop straight into the file.

Reusable Checklists

These are copy-paste ready for your firm SOP or a parent handout. Tick the boxes as you work, since the page saves your progress locally.

Keep 15101 Season From Stalling

Form 15101 work does not arrive on one tidy deadline. It trickles in all year as adoptions close, as the SSA issues each SSN (about 2 weeks once it has every required document, per the SSA Form SS-5 guidance), and as ATIN CP notices land in clients’ mailboxes. That steady drip is exactly what stalls in a busy practice, because no single date forces the handoff.

The fix is to make the ATIN-to-SSN transition a named step in your workflow rather than a loose to-do. When each notice has an owner, a reply method, and a proof requirement, the update clears before it ages into a mismatch on next year’s return.

• Pair every ATIN CP notice with its correct next step: Form 15101 once the SSN is in hand, or Form 15100 if the ATIN is expiring with no SSN yet.
• Require the prior ATIN, the child’s new SSN, and both parents’ original signatures before any package moves to review.
• Lock the reply method to what the IRS instructions and your notice allow, since Form 15101 is submitted by fax or mail, not through an online upload tool.
• If a family’s address has changed since the ATIN was issued, write the new address in the address section on Form 15101.
• Log proof of submission and a follow-up date so a stalled update surfaces before the next filing.

When these updates compete with peak-season production, a structured delivery model keeps them moving. Our offshore tax preparation and review teams run that kind of SOP-driven workflow, so ATIN-to-SSN reporting clears on time without pulling senior reviewers off higher-value work.

FAQs

What documents do I need for the Adoption Tax Credit?

You will need your child’s SSN or ATIN plus adoption records and receipts that prove qualified expenses. If you used an ATIN during a pending adoption, update the IRS with Form 15101 as soon as you receive the SSN, then use the SSN on your tax return going forward. For EITC eligibility, an SSN is required.

How do I update Social Security after adoption?

You apply with the Social Security Administration for your child’s SSN. The SSA provides Form SS‑5 and instructions, and you must submit it with the required evidence documents or the SSA cannot process the application. Once the SSN is issued, send Form 15101 to the IRS to retire the ATIN and update your records.

What do I file if my ATIN is expiring and there is still no SSN?

Use Form 15100 to request a one‑year extension, following the reply options in your CP notice, including upload when offered. If the IRS needs more information, you may receive CP562C with a specific list of items to send.

Can I claim credits with an ATIN?

You cannot claim the Earned Income Tax Credit with an ATIN. An SSN is required for EITC purposes. Other items on your return may still use the ATIN while the adoption is pending.

Where do I mail W‑7A if I am just starting the process?

Mail W‑7A and placement documentation to the IRS ATIN Unit at Stop 6182 in Austin, or visit a TAC that will forward your package. The ATIN status line is 737‑800‑5511 if it has been at least 8 weeks.