IRS Letter 3064C is a request for documents. The IRS has flagged something on your return, usually a refundable credit tied to a qualifying child, and it is holding your refund until you prove the claim is legitimate. The wording varies from letter to letter because an IRS employee tailors it to your case, but the job in front of you is the same: send the specific proof the letter asks for, by the deadline printed on it, in a form the reviewer can match to your file.
Why You Got the Letter
The most common trigger is a credit claimed for a qualifying child. The IRS runs automated checks that compare your return against its own records, and any mismatch in the qualifying-child tests can produce this letter. Typical red flags include a child’s Social Security number appearing on more than one return, an address that doesn’t line up with other government records, or a relationship the IRS cannot confirm from its databases.1Internal Revenue Service. Dependents
Credits that most often draw verification are the Child Tax Credit (worth up to $2,200 per child), the Additional Child Tax Credit (up to $1,700), and the Earned Income Tax Credit.2Internal Revenue Service. Child Tax Credit Read your own letter carefully. It will name the tax year, the credit or claim at issue, and the specific tests the IRS wants documented.
What Documents to Send
In almost every 3064C case the request comes down to four things: that the child is related to you, lived with you long enough, meets the age requirement, and has a valid identification number. The IRS publishes worksheets that list every acceptable document: Form 886-H-DEP for dependents and Form 886-H-EIC for the Earned Income Tax Credit. Download them even if your letter didn’t reference them, because they tell you exactly what the reviewer will be looking for.
Relationship
For a biological child whose birth certificate lists you as a parent, the birth certificate alone is usually enough. If your name isn’t on the birth certificate, you’ll need adoption papers, a court order, or paternity test results.3Internal Revenue Service. Form 886-H-EIC – Documents You Need to Send to Claim the Earned Income Credit For a grandchild, niece, nephew, or sibling, send enough birth and marriage certificates to trace the family connection step by step. A stepchild takes both the child’s birth certificate and the marriage certificate linking you to the child’s parent.
Foster children are treated separately. The IRS accepts only a statement on letterhead from the authorized placement agency or a court document showing the placement during the tax year at issue.4Internal Revenue Service. Qualifying Child Rules A letter from the biological parent won’t work.
Residency
The child must have lived with you at the same U.S. address for more than half the tax year.1Internal Revenue Service. Dependents This is where most responses fail, because people send documents that cover only part of the year or send records that don’t show the child’s name alongside your address. You need records tying the child to your home for the required stretch of months. Acceptable options include:
- School records: enrollment forms, report cards, or attendance records showing the child’s name and your address.
- Medical records: doctor visit summaries, hospital records, or immunization records listing the child at your home address.
- Childcare records: daycare enrollment or payment records showing both names at the same address.
- Dated letters on official letterhead from a school, medical provider, social service agency, childcare provider, landlord, or place of worship confirming the child lived with you, with specific dates.5Internal Revenue Service. Form 886-H-DEP – Supporting Documents for Dependents
The IRS will not accept statements signed by a relative. A letter from your mother confirming the child lived with you carries no weight. Use independent third parties, and make sure the records collectively span more than six months.
Age
A qualifying child for the Child Tax Credit must be under 17 at the end of the tax year. For the Earned Income Tax Credit, the cutoff is under 19, or under 24 if the child was a full-time student for at least five months of the year. A child who is permanently and totally disabled qualifies at any age.4Internal Revenue Service. Qualifying Child Rules The birth certificate you gathered for the relationship test usually covers age too. If the child qualifies as a student, add school records showing full-time enrollment. If the child qualifies by disability, include a letter from a doctor or government agency confirming the condition.3Internal Revenue Service. Form 886-H-EIC – Documents You Need to Send to Claim the Earned Income Credit
Identity
Include a copy of the child’s Social Security card, or the ITIN assignment letter if the child has an Individual Taxpayer Identification Number instead. The number has to match what you reported. It sounds obvious, but leaving it out is a common reason responses get delayed.
How to Put Your Response Together
Your letter states a response deadline, typically 30 days from the date printed on the notice. Missing it can trigger an automatic denial, so work backward from that date. If you need more time, call the number on the letter and ask for an extension before the deadline passes.
Start with a short cover letter. Put your name, Social Security number, and the tax year at the top. Reference letter number 3064C and any control or case number printed on the notice. Then list each document you are enclosing so the reviewer isn’t guessing which paper proves which requirement.
Include a copy of the 3064C letter itself. It contains routing information the IRS uses to match your documents to your case.6Internal Revenue Service. Internal Revenue Manual 2.11.1 – IDRS Correspondence Send copies only. The IRS specifically instructs taxpayers never to send originals.7Internal Revenue Service. Topic No. 651 – Notices – What to Do Keep a full photocopy of everything you send, cover letter included.
Use the mailing address printed on your letter, not a general IRS address. Routing your response to the wrong processing center causes real delays. Send it by certified mail with a return receipt requested; the postmark proves you met the deadline and the tracking confirms delivery. If the IRS later claims it never received your package, that receipt is your defense.
You can also respond through the IRS Document Upload Tool, which is often faster and gives immediate confirmation. You’ll need either an access code (if your letter includes one) or the letter number, plus the name on the notice and your Social Security or taxpayer identification number. The tool accepts JPG, PNG, and PDF files. If your letter has no access code, you pick the letter number from a dropdown, and the IRS warns that selecting the wrong letter type can cause delays.8Internal Revenue Service. IRS Document Upload Tool
What Happens After You Respond
Expect a wait. Similar verification cases can take up to nine weeks after the IRS receives everything, and your refund stays on hold during that stretch. You can check status through “Where’s My Refund?” or the phone number on the letter, though phone waits are long during filing season.
If the reviewer finds your documents sufficient, the credit is approved and your refund is released. If more information is needed, you’ll get a follow-up letter asking for specific additional documents. Answer it promptly, because the clock resets each time the IRS asks for more.
If You Miss the Deadline or the Credit Is Denied
Ignoring the letter has both an immediate cost and a longer one. The IRS denies the credit, shrinking your refund by that amount. If you already received a refund based on the original return, you could end up owing money back.
On top of losing the credit, the IRS may assess an accuracy-related penalty of 20 percent on the underpayment tied to the disallowed credit.9Internal Revenue Service. Accuracy-Related Penalty Interest runs on any unpaid balance from the original due date until you pay in full, compounding daily at the federal short-term rate plus three percentage points.10Internal Revenue Service. Topic No. 653 – IRS Notices and Bills, Penalties and Interest Charges A separate penalty under IRC 6676 adds another 20 percent on the excessive portion of a refund or credit claim, though it doesn’t apply if the accuracy-related or fraud penalty already covers the same amount.11Internal Revenue Service. Erroneous Claim for Refund or Credit
If the IRS determines you claimed the credit with reckless or intentional disregard of the rules, it can ban you from claiming that credit for two years. A fraudulent claim carries a ten-year ban.12Internal Revenue Service. What to Do if We Deny Your Claim for a Credit The bans apply to the Child Tax Credit, Additional Child Tax Credit, Earned Income Tax Credit, Credit for Other Dependents, and American Opportunity Tax Credit. Multi-year bans do not apply to honest mistakes, but that call is made by an IRS employee reviewing your specific facts.
A denial isn’t necessarily permanent. To claim the same credit on a later return, you attach Form 8862. That requirement applies after any disallowance of the Earned Income Tax Credit (for tax years after 1996) or the Child Tax Credit, Additional Child Tax Credit, Credit for Other Dependents, or American Opportunity Tax Credit (for tax years after 2015), unless the denial was a simple math error. Filing without Form 8862 when it is required will get your return rejected. If you’re inside a two-year or ten-year ban, the IRS will reject an e-filed return that claims the credit during the ban period.13Internal Revenue Service. Instructions for Form 8862
You also have appeal rights. The denial letter explains how to request a conference with an IRS Appeals Officer, and you generally don’t need an attorney to do it.14Internal Revenue Service. Topic No. 151 – Your Appeal Rights If Appeals doesn’t resolve it, you can take the matter to Tax Court; the small-case procedure for disputes under $50,000 is designed to work without a lawyer, though professional help is worth considering if the facts are complicated.