Tax answer
How do quarterly estimated taxes work?
Short answer
Quarterly estimated taxes are prepayments of income tax and self-employment tax on income that has no withholding, such as 1099 or business income. You generally must pay them if you expect to owe about $1,000 or more after withholding and credits. Payments are due roughly mid-April, mid-June, mid-September, and mid-January. You avoid an underpayment penalty if your total payments cover at least 90 percent of this year's tax or 100 percent of last year's tax (110 percent if your prior-year income was high). In Florida there is no state estimated payment because there is no state income tax.
Why they exist
The tax system is pay-as-you-go. Employees meet that through payroll withholding. If you have income with no withholding — self-employment, a business, large investment gains, retirement distributions without withholding — you make estimated payments instead so the government is paid through the year rather than all at once.
Who has to pay
You generally owe estimated payments if both are true:
- You expect to owe at least about $1,000 when you file, after subtracting withholding and refundable credits, and
- Your withholding and credits are less than the smaller of 90% of this year's tax or 100% of last year's tax.
If you also have a W-2 job, increasing that withholding can substitute for estimated payments entirely.
The four due dates
Payments cover income in roughly these periods, due about:
| Payment | Income period | Due (approx.) |
|---|---|---|
| 1st | January – March | mid-April |
| 2nd | April – May | mid-June |
| 3rd | June – August | mid-September |
| 4th | September – December | mid-January of next year |
The periods are uneven on purpose. You pay with Form 1040-ES vouchers or online through IRS Direct Pay or your IRS account.
The safe harbor — how to avoid a penalty
You will not owe an underpayment penalty if your combined withholding and timely estimated payments equal at least:
- 90% of the tax on this year's return, or
- 100% of last year's total tax (110% if your prior-year adjusted gross income was over $150,000).
The prior-year safe harbor is popular because you know the number in advance — divide last year's tax by four and pay that each quarter.
Uneven income
If your income is seasonal or lumpy, paying four equal amounts can either overpay early or trigger a penalty for a quarter when you earned a lot. The annualized income installment method lets you pay based on what you actually earned each period. It takes more calculation but can lower both the payments and the penalty.
If you underpay
The penalty is calculated quarter by quarter, based on how much you were short and an interest rate the IRS sets. It is reported on Form 2210. Filing and paying the balance stops it from growing; catching up a missed quarter as soon as possible limits it.
Frequently asked questions
- What if I miss a quarter?
- Pay it as soon as you can. The penalty accrues from the due date to the date you pay, so a late payment is better than skipping it.
- Can I just pay it all at the end?
- You can, but a lump sum in January does not undo the penalty for the earlier quarters when the income was earned. Withholding is the exception — it is treated as paid evenly no matter when in the year it happens.
- Do I need to pay Florida estimated taxes?
- No. Florida has no state income tax, so there is no state estimated payment.
- How do I figure the amount?
- Estimate your expected income, subtract expenses and deductions, calculate income tax plus self-employment tax, subtract withholding and credits, and divide by four — or use the prior-year safe harbor. Ross can calculate this and prepare the vouchers.
- I overpaid my estimates. What happens?
- The overpayment becomes a refund or can be applied to next year's first estimated payment.
Written by Ross of TaxesbyRoss. Last reviewed September 1, 2026. Reflects the 2025 tax year — rules and figures change annually. This is general information, not individualized tax advice; your result depends on your own facts and records.
Want this handled for your situation?
See 1099 & Self-Employed Taxes, or talk it through with Ross.