Delaware quarterly taxes are the estimated income tax payments you owe the Delaware Division of Revenue when your tax for the year, minus withholding and credits, will come to more than $800. You pay in four installments due April 30, June 15, September 15, and January 15 of the following year. Miss an installment or pay too little, and the state adds a 1½% monthly penalty plus 0.5% monthly interest until you catch up.
Who Has to Pay
The rule applies to every Delaware resident and every nonresident with Delaware-source income whose expected net tax liability exceeds $800 after withholding and credits.1State of Delaware. Declaration of Estimated Income Tax for Individuals 2026 Instructions Residents are taxed on income from anywhere; nonresidents only on what Delaware sourced.
In practice, this catches people with self-employment profits, partnership or S-corporation income, rental properties, capital gains, interest, and dividends. If you draw a W-2 salary and your employer withholds Delaware tax, you’re usually covered without quarterly payments. The test is simple arithmetic: project your Delaware tax for the year, subtract what will be withheld and any credits, and see whether more than $800 remains.
Farmers and Fishermen
If at least two-thirds of your gross income comes from farming or fishing, Delaware applies a reduced safe harbor of 66⅔% of the current year’s tax instead of the standard 90%.2State of Delaware. Declaration of Estimated Income Tax for Individuals 2024 Instructions
How Much to Pay Each Quarter
You have two safe harbors, and you only have to meet the smaller of them to avoid a penalty: 90% of what you’ll actually owe this year, or 100% of what your return showed last year. The prior-year number is the one most people use because it’s already settled. If your federal AGI on last year’s return topped $150,000 ($75,000 if married filing separately), the prior-year figure rises to 110%.2State of Delaware. Declaration of Estimated Income Tax for Individuals 2024 Instructions Take the smaller safe harbor amount, subtract any withholding you expect, and divide the rest by four.
If you’d rather project the current year directly, Form 200-ES includes a Tax Computation Schedule and worksheet. Delaware starts with your projected federal adjusted gross income, subtracts Delaware’s standard deduction of $3,250 for single filers or $6,500 for married filing jointly (or your itemized deductions if higher), applies the state’s graduated rates topping out at 6.6% on income over $60,000, and then subtracts personal credits.1State of Delaware. Declaration of Estimated Income Tax for Individuals 2026 Instructions3Division of Revenue – State of Delaware. Tax Rate Changes Most taxpayers get $110 per personal exemption claimed on the federal return, with another $110 at age 60 or older.4Delaware General Assembly. House Bill No. 158 Qualifying lower-income workers with W-2 or 1099-NEC income between $18,000 and $36,000 (and AGI not above $36,000) receive $330 per exemption instead.5Delaware General Assembly. House Bill No. 321
The Four Due Dates
Delaware’s calendar does not match the federal one. First-quarter payments are due April 30, two weeks after the IRS April 15 deadline. The remaining installments fall on June 15, September 15, and January 15 of the following year.1State of Delaware. Declaration of Estimated Income Tax for Individuals 2026 Instructions If a date lands on a weekend or state holiday, you have until the next business day.
Those intervals aren’t even. Six weeks separate the first and second payments, then three months to the third, then four months to the last. You can also pay the entire year’s estimate on April 30 if you prefer to be done with it.
Farmers and fishermen operating under the two-thirds rule can skip the four-installment schedule entirely: pay once by January 15, or file the full annual return and pay all tax owed by March 1.6Internal Revenue Service. Farming and Fishing Income
How to Submit Payments
Pay electronically through the Delaware Taxpayer Portal.7State Department of Revenue. Submit an Estimated Payment – Delaware Taxpayer Portal Direct debit from a checking or savings account is free and lets you schedule the payment for any date up to the deadline. Credit card is accepted but capped at $10,000 per transaction and comes with a processor convenience fee, usually around 2.5%.2State of Delaware. Declaration of Estimated Income Tax for Individuals 2024 Instructions On a $5,000 payment that fee runs roughly $125.
Prefer paper? Mail a check or money order with the Form 200-ES voucher to the address printed on it. Make it payable to the Delaware Division of Revenue, write your Social Security number and the tax period on the check, and don’t staple anything together. The postmark date counts as the payment date, so a check mailed on the due date is on time even if it arrives later.
If You Underpay
When your withholding and estimated payments together don’t meet one of the safe harbors, Delaware charges a penalty of 1½% per month on the amount of each underpaid installment, assessed quarter by quarter.8Division of Revenue – State of Delaware. Personal Income Tax FAQs Interest also runs on the unpaid tax at 0.5% per month, compounding monthly from the due date.9Justia. Delaware Code Title 30 Chapter 5 Subchapter III 533
The numbers add up quickly. Miss a $2,000 installment entirely and go six months before catching up, and you owe $180 in penalty plus about $60 in compounding interest. The penalty applies even when your eventual annual return shows a refund. What matters is whether each installment was adequate on its own due date.
You calculate the penalty yourself on Form PIT-UND. Part 2 (the Short Method) works if your payments were equal and on time, or if you made none. Part 3 handles unequal or late payments and the annualized income method.10Delaware Division of Revenue. Delaware Underpayment of Estimated Taxes Form PIT-UND Instructions
When the Penalty Can Be Waived
Delaware will consider a waiver in two situations: the underpayment resulted from a casualty, disaster, or other unusual circumstance, or you retired after age 62 or became disabled during the current or prior tax year.10Delaware Division of Revenue. Delaware Underpayment of Estimated Taxes Form PIT-UND Instructions If one of these applies, skip Form PIT-UND with your return. The Division of Revenue will assess the penalty, and you then request a waiver by writing to the Tax Conferee at the Division of Revenue.
When FEMA declares a federal disaster, the IRS postpones affected deadlines, including estimated installments within the postponed window.11Internal Revenue Service. IRS Announces Tax Relief for Taxpayers Impacted by Severe Storms Whether Delaware matches the postponement depends on the event, so watch for Division of Revenue announcements if a disaster hits your area.
When Your Income Is Lumpy
Four equal payments make sense when income flows evenly. They don’t when a big capital gain lands in November, or when a seasonal business earns most of its money in the second half of the year. Paying a quarter of the annual total each April means handing the state cash months before you’ve actually earned the income behind it.
The annualized income installment method matches payments to when income arrives. Complete Part 3 of Form PIT-UND.10Delaware Division of Revenue. Delaware Underpayment of Estimated Taxes Form PIT-UND Instructions The form breaks the year into four cumulative periods — January through March, January through May, January through August, and the full year — and calculates each installment from the income and deductions actually realized by that point. The math is tedious, but it can eliminate penalties on early quarters when little income had come in.
Whatever method you use, save every receipt. Hold onto the portal confirmation or a copy of the check and voucher, and keep the worksheets showing how you arrived at each quarter’s number. If the Division of Revenue questions a payment later, those records are what settle it.