The CP45 is a confirmation notice. You elected on your return to have your overpayment applied to next year's estimated taxes rather than receiving it as a refund. The CP45 confirms that the application was processed. This is similar to the CP10 but may appear in different processing contexts.
Why This Matters
The applied overpayment counts as a first-quarter estimated tax payment for the following year. Make sure you factor this into your quarterly payment calculations. If you applied $4,000 and your total estimated tax obligation is $16,000 for the year, you need to pay $12,000 across the remaining three quarters, not $16,000.
If You Changed Your Mind
Once the overpayment has been applied to estimated tax, reversing the election is difficult. You generally can't get a refund of the applied amount once it's been processed. If you need the money back, you may need to adjust your future estimated payments downward and wait for the overpayment to work itself out through the annual return cycle.
Verify the Amount
If the IRS adjusted your return and the overpayment changed, the applied amount on the CP45 will differ from what you elected. Review any accompanying adjustment notices to understand why the amount changed.
If the applied amount doesn't match your records, call us at (813) 229-7100.