Why Is My Refund Different from What I Expected?

Your refund may differ from what you expected because the IRS found a math error, identified income you did not report (such as a 1099 you forgot), adjusted a credit claim, or applied a refund offset for past-due debts like student loans or child support. In each case, the IRS sends a notice explaining the adjustment. Below are the most common reasons for refund discrepancies and what to do about each one.

Why refunds differ from expectations

When you file your tax return, your tax software or preparer calculates an expected refund based on the information you entered. The IRS then processes the return independently, matching your reported income against W-2s, 1099s, and other information returns filed by employers, banks, and other payers.

If the IRS finds a discrepancy between what you reported and what third parties reported, or if it identifies an error on your return, it adjusts the refund accordingly. You may receive more or less than you expected.

Math errors on the return

The IRS has authority to correct simple math errors without auditing your return. Common math errors include:

• Adding or subtracting income lines incorrectly
• Applying the wrong tax rate to a bracket
• Miscalculating a credit or deduction
• Entering the wrong standard deduction amount
• Transposing digits in income or withholding amounts

When the IRS corrects a math error, it sends a CP12 notice explaining the change. The corrected refund (higher or lower) is issued automatically. You do not need to take action unless you disagree with the correction.

Missing income (1099s you forgot)

If you received a 1099-NEC (freelance income), 1099-INT (interest), 1099-DIV (dividends), 1099-B (investment sales), or 1099-G (unemployment), the payer also sent a copy to the IRS. If you did not include that income on your return, the IRS will add it and recalculate your tax.

This is one of the most common reasons for a smaller-than-expected refund. For example, if you forgot to report $2,000 in freelance income from a 1099-NEC, the IRS adds it to your income and increases your tax by the applicable bracket rate, reducing your refund by hundreds of dollars.

To avoid this, wait until you have received all income documents before filing. Most 1099s are due to recipients by January 31.

Changes to credits (CTC, EITC)

The IRS may adjust your refund if it determines you do not qualify for a credit you claimed, or if the credit amount was calculated incorrectly:

• Child Tax Credit: If a child does not meet the age test (under 17), residency test (lived with you more than half the year), or SSN requirement, the IRS will disallow the $2,200 credit for that child.
• EITC: The IRS may disallow the EITC if your income exceeds the limit, if a qualifying child does not meet requirements, or if there is a discrepancy in reported earned income.
• Education credits: The American Opportunity or Lifetime Learning Credit may be adjusted if the reported tuition does not match Form 1098-T from the educational institution.

EITC verification delays

Even when the IRS does not change the EITC amount, it may delay your refund to verify your eligibility. The PATH Act requires the IRS to hold refunds claiming EITC or ACTC until mid-February (see our PATH Act hold guide).

In some cases, the IRS sends a letter requesting additional documentation to verify EITC claims. This can delay your refund by weeks or months if you need to respond with proof of income, residency, or the qualifying child's relationship to you.

Refund offsets (student loans, child support)

The Treasury Offset Program (TOP) allows federal and state agencies to intercept your tax refund to cover certain debts. Common debts that trigger offsets include:

• Past-due federal income tax
• Past-due state income tax
• Past-due child support
• Defaulted federal student loans
• Certain other federal agency debts (e.g., overpaid unemployment benefits)

If your refund is offset, you will receive a notice from the Bureau of the Fiscal Service explaining how much was taken and which agency received it. The remainder of your refund (if any) is deposited or mailed to you as usual.

If you file a joint return and only one spouse owes the debt, the other spouse can file Form 8379 (Injured Spouse Allocation) to recover their portion of the refund.

IRS adjustments and notices

When the IRS adjusts your refund, it sends a notice explaining the change. Common notices include:

• CP12: Math error was corrected; your refund was changed.
• CP49: Part or all of your refund was applied to a past-due tax balance.
• CP11: Changes were made to your return; you now owe a balance.
• Letter 5071C: Identity verification needed before your refund can be released.

Always read IRS notices carefully. They include an explanation of the change and instructions for how to respond if you disagree.

What to do if your refund is wrong

If your refund is different from what you expected, follow these steps:

1. Wait for the IRS notice. The IRS will send a letter explaining any adjustment. This usually arrives within a few weeks of the refund being issued.
2. Review the notice carefully. Compare the IRS's figures to your filed return. Check for math errors, missing income, or credit adjustments.
3. If you agree with the change: No action needed. The adjusted refund is correct.
4. If you disagree: Follow the instructions on the notice. You may need to call the IRS, submit documentation, or file an amended return (Form 1040-X).
5. Keep records. Save all IRS correspondence and copies of your filed returns for at least three years.

To estimate your refund accurately before filing, use the tax refund estimator and make sure to include all income sources, credits, and deductions.