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Your IRS CP21B Notice, Explained
Also called: Notice CP21B
Last reviewed 2026-07-12
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What this notice usually means
IRS Notice CP21B tells you the IRS made the changes you requested to your tax return. You should get your refund within 2 to 3 weeks of the date on your notice. If you disagree with the changes, the notice gives you a number to call.
See every source line for this notice
“We sent you this notice because we made the changes you requested to your tax return for the tax year specified on your notice. You should receive your refund within 2-3 weeks of your notice.”
“Correct the copy of your tax return that you kept for your records.”
“Be sure to report any interest we paid you on your tax return for this year.”
“If you don't owe other taxes or debts we're required to collect, such as child support, and 3 weeks have lapsed, call us at number shown in the “What you need to know” section of your notice.”
“If you receive $10 or more in interest, you'll receive a Form 1099-INT, Interest Income, by Jan. 31 of next year.”
What to do now
- 1
Wait 2 to 3 weeks for your refund
The IRS expects your refund to arrive within 2 to 3 weeks of the date on your notice.
- 2
Call the IRS if your refund does not arrive
If 3 weeks pass with no refund and you do not owe other taxes or debts, call the number in the notice.
- 3
Correct your own copy of your return
Update the copy of your tax return that you kept for your records to match the changes.
- 4
Report any interest paid to you
If the IRS paid you interest, report that amount on your next tax return. A Form 1099-INT arrives by Jan. 31 if it is 10 dollars or more.
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Sources
- Internal Revenue Service (irs.gov)Retrieved 2026-07-12
Last reviewed 2026-07-12
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