Letter 12C: The IRS Needs More Information to Finish Your Return

Why you might get this

• Your Form 1040 or 1040-SR was missing a form or schedule that supports something you claimed.
• The IRS needs to verify your income, withholding, or credit amounts.
• The IRS needs to confirm a taxpayer identification number or Social Security number on your return.

The deadline

Send the requested information by the date printed on your letter. The IRS says a refund you're owed will usually arrive about 6 to 8 weeks after they receive your response, so replying promptly keeps your return moving.

This notice doesn't carry a fixed response deadline, but it still deserves attention — see what to do below.

What to do

1. Read your letter carefully to see exactly what information the IRS is asking for.
2. Gather the missing forms, schedules, or documents that support your entries.
3. Send the requested information to the IRS by the date shown on your letter.
4. Respond even if you disagree, and include a clear written explanation of what you disagree with.
5. Do not file a Form 1040-X (Amended U.S. Individual Income Tax Return) to fix this — just send what the letter asks for.

What happens if you ignore it

If you don't respond, the IRS can't finish processing your return, which means any refund you're owed will be delayed or held until they get what they need.

If you need help, you can authorize someone to represent you before the IRS, and you may qualify for free help from the Taxpayer Advocate Service (TAS) or a Low Income Taxpayer Clinic.

What Letter 12C Means

Getting a Letter 12C doesn't mean you did anything wrong — it just means the IRS needs a little more from you before they can finish processing your income tax return. Maybe a form or schedule was left out, or the IRS wants to double-check your income, withholding, credits, or a Social Security number.

The good news: this is usually a quick fix. Read your letter closely to see exactly what's being requested, then send that information back by the date printed on your notice. If you're expecting a refund, the IRS says it typically arrives about 6 to 8 weeks after they receive your response.

A few tips: respond even if you disagree, and explain your side clearly in writing. Don't file an amended return (Form 1040-X) to handle this — just send what the letter asks for. Keep copies of everything you send.

If you feel stuck, you can get someone to represent you, or reach out to the Taxpayer Advocate Service or a Low Income Taxpayer Clinic for free help.

Want a little peace of mind? Solace can keep an eye on your IRS account and let you know when things change.