If a capital gain will leave you owing at least $1,000 in federal tax beyond what your withholding and refundable credits cover, you generally need to pay estimated taxes on capital gains through quarterly payments on Form 1040-ES.1Internal Revenue Service. Estimated Tax – FAQs2Internal Revenue Service. About Form 1040-ES, Estimated Tax for Individuals Investment profits don’t have tax withheld the way a paycheck does, so the IRS expects you to pay in during the year rather than settling up at filing time.
There is a way out of the $1,000 rule: the safe harbors. You can skip estimated payments (or pay less) if your withholding and estimated payments together will cover the smaller of 90% of this year’s tax or 100% of last year’s tax. If your prior-year adjusted gross income was more than $150,000 ($75,000 if married filing separately), that second figure rises to 110%.3Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty The prior-year test is the one most people rely on, because the number is already fixed. If your total tax last year was $30,000 and your AGI was under $150,000, paying in $30,000 this year through withholding and quarterly payments protects you from a penalty even if a large gain drives your actual bill much higher.
The typical trigger looks like this. Someone whose W-2 withholding normally lines up with their tax bill sells an investment property or a long-held stock position, realizes a six-figure gain, and their withholding no longer comes close to either safe harbor. That gap is what quarterly payments (or extra withholding) are meant to fill.
The Withholding Shortcut That Avoids Quarterly Payments
If you have a W-2 job, you may not need to file a 1040-ES at all. The IRS treats income tax withheld from wages as paid in four equal installments across the year no matter when it was actually taken from your paycheck.4Internal Revenue Service. Publication 505, Tax Withholding and Estimated Tax That has a useful consequence: if you sell in October and file a new W-4 asking your employer to withhold extra, the IRS treats that withholding as if it had been paid evenly since January. It retroactively covers the earlier quarters.
For a moderate one-time gain, bumping up withholding on your remaining paychecks can eliminate the need for estimated payments entirely.1Internal Revenue Service. Estimated Tax – FAQs For a very large gain, it may not be enough on its own, but it will shrink whatever you need to send through 1040-ES.
Figuring Out How Much to Pay
To size the payment, project your total income for the year and apply the right rate to each piece. Short-term gains (assets held one year or less) are taxed at ordinary income rates, which for 2026 run from 10% up to 37%.5Internal Revenue Service. Federal Income Tax Rates and Brackets Long-term gains (more than one year) get preferential rates of 0%, 15%, or 20% depending on your taxable income.6Internal Revenue Service. Topic No. 409, Capital Gains and Losses Most sellers of long-held investments land in the 15% bracket.
Two special rates catch people off guard. Collectibles like art, coins, antiques, and precious metals carry a maximum long-term rate of 28%. And the portion of a gain on depreciated real estate that reflects depreciation you previously deducted (unrecaptured Section 1250 gain) is taxed at up to 25%.6Internal Revenue Service. Topic No. 409, Capital Gains and Losses If you’re selling a rental or a coin collection, those higher rates change your estimated payment.
Don’t Forget the Net Investment Income Tax
A 3.8% surtax applies to net investment income (including capital gains) once modified AGI exceeds $200,000 single, $250,000 married filing jointly, or $125,000 married filing separately.7Internal Revenue Service. Net Investment Income Tax The tax applies to the lesser of net investment income or the amount your MAGI exceeds the threshold. A married couple with $300,000 in MAGI and $225,000 in net investment income pays 3.8% on $50,000, the excess over $250,000.8Internal Revenue Service. Questions and Answers on the Net Investment Income Tax These thresholds aren’t indexed for inflation. If you skip the NIIT in your projection, your estimated payment will be short.
Net Your Losses First
Before you calculate anything, net your gains against any capital losses realized in the same year. Short-term losses first offset short-term gains; long-term losses first offset long-term gains. Any leftover loss in one category then offsets gains in the other.6Internal Revenue Service. Topic No. 409, Capital Gains and Losses If total losses exceed total gains, you can deduct up to $3,000 of the excess against ordinary income ($1,500 if married filing separately), and the rest carries forward indefinitely.9Office of the Law Revision Counsel. 26 USC 1211 – Limitation on Capital Losses
One trap: the wash sale rule. If you sell a security at a loss and buy the same or a substantially identical security within 30 days before or after, the loss is disallowed for the year and added to the basis of the replacement shares. If you’re harvesting a loss to offset a gain for estimated tax purposes, stay out of that 30-day window.
Exclusions That Reduce or Eliminate the Gain
Selling your main home? You can exclude up to $250,000 of gain if single, $500,000 if married filing jointly, provided you owned and lived in it for at least two of the five years before the sale.10Internal Revenue Service. Topic No. 701, Sale of Your Home Only the excess over the exclusion is taxable, so many home sales trigger no estimated payment at all.
Investment real estate can be rolled into a like-kind Section 1031 exchange, deferring the gain entirely if you identify a replacement within 45 days and close within 180 days.11Internal Revenue Service. Like-Kind Exchanges Under IRC Section 1031 Gains reinvested into a Qualified Opportunity Fund within 180 days are also deferred, but note that any remaining deferred QOF gains must be recognized on December 31, 2026 whether or not you’ve sold the investment.12Internal Revenue Service. Opportunity Zones Frequently Asked Questions If you have prior QOF deferrals, build that forced income into your 2026 estimated payments.
Quarterly Deadlines
The federal estimated tax calendar covers uneven periods:13Internal Revenue Service. Individuals 2
- First quarter (January 1 – March 31): due April 15
- Second quarter (April 1 – May 31): due June 15
- Third quarter (June 1 – August 31): due September 15
- Fourth quarter (September 1 – December 31): due January 15 of the following year
When a due date falls on a weekend or federal holiday, it moves to the next business day. Taxpayers in FEMA-designated disaster areas get automatic extensions with no application needed.14Internal Revenue Service. IRS Reminder: Disaster Victims in Twelve States Have Automatic Extensions to File and Pay Their 2024 Taxes
The IRS accepts payments through Direct Pay from a bank account and through the Electronic Federal Tax Payment System, which requires enrollment ahead of time. You can also mail a check with a 1040-ES voucher.15Internal Revenue Service. Payments If a gain hits after you’ve made earlier quarterly payments, size up the remaining ones. If a later loss reduces your projection, size the remaining payments down.
When Your Gain Lands Mid-Year
The standard system assumes income arrives evenly across four quarters. Capital gains rarely cooperate. Sell in September and the default calculation can look as though you underpaid in April and June, even though the income didn’t exist yet.
The annualized income installment method fixes this. It recalculates the required payment for each quarter based on income actually received through the end of that period. You report it on Schedule AI of Form 2210, attached to your annual return.16Internal Revenue Service. Instructions for Form 2210 It’s more paperwork, but it prevents penalties for quarters before the gain occurred, and it can matter a lot when a big sale closes late in the year.
What Happens If You Underpay
The underpayment penalty functions like interest. The IRS applies its underpayment rate, currently 7% per year for individuals, to each quarter’s shortfall from the day that payment was due until you pay it or reach the filing deadline.17Internal Revenue Service. Interest Rates Remain the Same for the First Quarter of 2026 The rate is the federal short-term rate plus three points and adjusts every quarter.18Internal Revenue Service. Quarterly Interest Rates
The penalty is computed automatically on your return; it isn’t discretionary. Meeting either safe harbor is the reliable way to avoid it.19Internal Revenue Service. Topic No. 306, Penalty for Underpayment of Estimated Tax3Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty16Internal Revenue Service. Instructions for Form 2210 Outside those, the penalty holds.
State Payments Are a Separate Question
Federal estimated tax isn’t the whole picture. Most states that levy an income tax also require quarterly estimated payments and tax capital gains at ordinary income rates rather than at preferential federal rates. Only about eight states apply reduced rates to long-term gains, and seven have no individual income tax. If you live in one of the roughly 32 states that treat gains as ordinary income, the combined bill can be considerably larger than the federal number alone. State schedules usually mirror the federal quarterly dates, and states impose their own underpayment penalties. Check your state’s rules alongside the federal calculation.