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

Content provided for general information. Talk to your tax advisor to confirm the details for your specific situation before taking action.

IRS Letter 12C (officially labeled LTR0012C) is a notice that the IRS needs more information before it can process your return. The most common reason is a missing form.

Why does the IRS send letter 12C?

The IRS sends this letter for three reasons.

  • Missing forms or schedules on an individual tax return.
  • Verification of income, withholding, or credit amounts. For example, a missing W-2.
  • Documentation needed to reconcile advance payments of the Premium Tax Credit (Obamacare subsidy).

The letter does not mean you did or did not correctly calculate your taxes. It simply means the IRS needs more information to verify your Form 1040 individual income tax return.

In some cases, you may also receive IRS Notice 1445 which simply tells you how to get help in another language.

What should you do in response to Letter 12C?

The IRS will tell you exactly what information they need. This might be a form you receive from an employer or health insurance provider, or it could be a form or schedule you were supposed to complete when you filed.

There are three general outcomes.

  • You track down the requested forms and they exactly match your tax return, so there should be no changes to your taxes owed.
  • The documents don’t match your tax return, so the IRS will recalculate your taxes owed. If you underpaid, interest and penalties may be added.
  • You can’t find the requested information, which may lead to the IRS disallowing deductions or credits, using its own calculations, or performing an audit.

If you’re in the first category, it’s probably safe to return the required forms as instructed in the letter. If not, you may wish to seek professional advice about whether you can avoid penalties and how to support your tax return.

Premium Tax Credit Issues

The IRS is often very strict about the premium tax credit. It will usually only go by your 1095-A even if you can clearly show that your 1095-A is incorrect.

You will need to get a new health insurance marketplace statement showing the correct information for the IRS to process your tax return.

Should you file an amended tax return?

The IRS generally recommends that you do not file an amended tax return. It will make any necessary adjustments to your original return based on the information you provide.

However, if you discover additional errors or find that the information substantially changes your tax return, it may be in your best interest to go ahead and amend your return.

What happens if the amount you owe changes?

If the amount you owe changes, the IRS will send you a bill. You have several options depending on whether you agree or disagree with what you owe.

If you underpaid your tax, interest and penalties will usually apply from the original due date of the return. To reduce the penalties and interest you’ll have to pay, make payment arrangements as soon as possible.

How long do you have to respond to Letter 12C?

The deadline to respond is generally 20 days from the date on the top of the letter. Check the specific instructions in your letter. Where to send your response can vary based on where you live, so be sure to use the mailing address or fax number on the letter you got from the IRS rather than looking it up online.

If you disagree with the letter, are unsure how to respond, or believe it may lead to penalties, you should contact an Enrolled Agent or other tax professional immediately.

If you ignore the letter, you might find yourself faced with a certified letter from the IRS.

How long does it take the IRS to respond?

When you respond to an IRS letter, they will usually review your response in six to eight weeks. However, many taxpayers have been reporting that they are taking much longer to respond recently.


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28 thoughts on “IRS Letter 12C: The IRS Needs More Information to Process Your Return”

  1. Really confused as well spoke with advocate month and a half ago and she said if you don’t receive your refund in a month call us back we’ll it’s been a month and a half I call today and I am just hearing about this 12c form they said they maild it out feb 1.0 2023 but I never received it anyways I have been waiting over 2 1/2 years now I really don’t understand why they didn’t say anything about this a month and half ago when I spoke with them.

  2. E Filed my 2021 taxes thru a tax company on 3-8-2022.Got my 12C on 3-13-2922.Sent off needed more info certified mail on 3-25-2022 tried sending it by fax on 8 different occasions fax line always busy..Got hung up on intentionally by IRS agent from West Virgins within 5 minutes after waiting 2.5 hrs to speak to him ..8-9-2022 and I am still waiting for my refund that is still being processed…👎🏻

  3. i got a 12c letter june 22 about my 2020 taxes (this was almost a month ago) and my taxes were processing until a few days when my irs2go app stopped showiing my progress. Now when i put in my info it says “information does not match” i respoded to the letter within days of receiving the letter and now my progress has ended and no letter from either. what can i do

    • You may be receiving another letter, or you can call the IRS number on your original letter to check the status.

  4. I received LTR 12C just now. how do I find out what tax year IRS is talking about? Top sentence read ” we received your Dec 31, 2018, form 1040…’ Looking for clarification for Form 6251. I assumed tax year 2018, I searched and I did not find the figure mentioned for Form 6251.
    If I know what tax year IRS is asking, perhaps I can search further. Please Help.

    • This could be really complicated because of how long ago it was and because it seems to involve AMT. I strongly recommend you schedule a consultation with a local tax pro.

    • If you still have your letter, the address should be on it. You can also check your online account to see if it’s there (not all letters are). If not, you’ll need to call the IRS.

      The reason the IRS doesn’t publish the addresses or fax numbers is that they can vary based on where you live and your specific situation. Two people who get the same letter may need to respond to different places.

  5. My ex-husband received a letter 12C in March 2022 with both of our names at the top regarding 2021 taxes. Our divorce was final in April 2019. That was the last year we filed as married. In addition, he received a 2021 Form 1040-V Payment Voucher form in the mail with just his name on it. I have tried repeatedly to call the IRS phone number on the copy of the letter he sent me. After clicking through the prompts, it says they are busy and to call back later. Am I responsible for this information if I was divorced in 2019?

    • This is definitely something you should look into to find out why your info is still tied to his. Even if you’re not responsible in the end, you want to make sure there isn’t anything crossed that can cause more problems you have to deal with.

  6. I received 12c letter 9/4/2020. I responded within 5 days with everything they needed. I kept trying the irs app to check status. it was still saying no date aat this time. As of 1-1-2021 everywhere I check it has no information. i have called so many times to talk to someone, and finally someone outside the irs gave me new number. Since 1-10-2021 i have called spoken to 5 different individuals, & they all, but one, say the same thing. There is no record of my filing & that i should think about going to an agent to possibly refile cause mybe it wa rejected, which only one person told me that. the other person One irs worker told me that my info they requested was received, but that there is no record of it anywhere T THIA TIME OF EVEN BEEN FILED. I TOLD HER that the state taxes i filed were returned and applied to fines. I am really tired of checking my account, the internet & the irs and calling. i finally went to H&R to file this years, 1st time not doing it myself, someone implied sending them back in cause they see no record anywhere also. So, i am doing just that. even if it takes another 2 years, covid aside, there should at least be record of where it is. this years i am afraid to file.

  7. We got a letter in August of 2020 stating you needed more info on our 2019 taxes. Our tax preparer sent everything in on September 8th,2020. have not received any information on our tax return. we were due a refund. I called yesterday and was talking to someone, she was working on it while talking to me and somehow we got cut off. I haven’t been able to get through on the phone now. Any idea whats going on with our return?

    • This is not the IRS. You will need to call the IRS until you get through. If you filed on paper, they are months behind on processing those.

  8. I filed my 2019 taxes on 4/23/2020. I received a letter 12C in september of 2020 and responded within 20 days. I still have not gotten a 2019 tax refund or any other sort of correspondence from the IRS. Every time I have called, the person has said that they “see it as processing” and to call again in 30 days. When I check “Where’s my refund” it gives me an error notice. Is this going to impact my 2020 tax return/refund?

    • There are currently severe processing delays at the IRS. Whether it would affect a different year depends on exactly what the issue is. The IRS is the best source of information despite the hold times. If you go to someone local, they may be able to give more information based on exactly what your form says.

  9. I received a letter recently regarding my 2018 tax return, stating “Schedule 1 incomplete or missing” and “Schedule 4 incomplete or missing” in 2020.
    Also, it has my then ITIN to which I already requested to have everything moved to my new SSN.
    I’m confused why they are requiring more information when I already paid the late fees when they billed me, confirming that I’ve paid the amount of the tax owed.

    Am I being audited for this?

    • IRS bills are based on your original tax return or IRS adjustments and don’t confirm that the calculation of what you owed was correct. The IRS has now decided there is something it needs to verify that could potentially result in changes to your return.

  10. I was put into this plan by an agent who called to help me decide which insurance plan would best suit me since I recently retired early and had to wait one year until I was eligible for medicare. This was a mistake, my income was greater than the required income to be a part of this program, according to my calculations I will now owe THOUSANDS of dollars to the IRS on top of the premiums that I paid for the inadequate insurance that most doctors did not want to accept. I cannot reach anyone at the IRS and I am stuck with this bill that I was misguided into accepting. The system is broken and the citizens are left with paying the consequences for a broken system. I am stuck now between a rock and a hard place.

    • This sounds like something you want to get a consultation with an attorney on regarding whether the agent is liable for the extra money you had to pay.

  11. I received letter 12C about a 1095A form concerning information from the Market Place Insurance, they have been contacted twice and saying they mailed the form out but I never received it. What can I do to get my refund which is much needed, this have been going on since I received that 12C letter on March 11, 2020.

    • Have you tried seeing if you can get your form online from the Marketplace? Do they have your correct address?

  12. I filed in dec 31 they sent me a letter saying they needed the healthcare paper i took it right to my accountant she faxed it right over. im still waiting for my refund its been almost 4 months please help me

    • You can try checking your IRS account transcript online or calling them (if you can get through now), but you really need to go back to your accountant since she knows the full details.

  13. I received my 12c paper. Sent in all documents the asked for. What I want to know is how long will it take to look over documents? By what the letter states you have to respond within 20 days, but do to the covid-19 where does that leave me, because I out of work with no job, and I have a household to support and I have been waiting patiently.

  14. The LTR 12C letter from IRS office in Kansas City is asking for a confirmation of my social security Number because according to the social security administration my social security number matches that of a person who is deceased. I checked my 2019 tax return and my SS# is correct on all pages, Fed and State.
    THIS LOOKS LIKE A SCAM and all IRS offices are temporarily closed for the virus.
    Please suggest a direction

    • The IRS still does have limited phone support at this time via their main number, but I don’t know if they have people in that can tell you if the notice is legit or why they sent it. You could also try visiting and trying to look up your information there. Checking your credit reports and monitoring for possible identity theft until you can get an answer would also be good ideas.

    • Hi Charles, I just got a letter from IRS with same information, saying my social number matches of a person who is deceased. How did you get his resolved? Was this a scam? Thanks for your help.


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