You have to file a Delaware state tax return if you’re a full-year resident whose Delaware adjusted gross income crosses the threshold for your age and filing status, if you’re a nonresident who earned any income from a Delaware source, or if you’re a part-year resident with income during your Delaware period or Delaware-sourced income afterward. You should also file if Delaware tax was withheld from your pay and you want it back, even when no return is otherwise required.
Figure Out Your Residency Category First
Delaware sorts individual taxpayers into three buckets, and which one you’re in decides the rest.
You’re a full-year resident if your permanent legal home was in Delaware for the whole tax year. Permanent legal home means the place you intend to return to after any temporary absence, not just where you slept most nights. Delaware also treats you as a resident under a separate rule: if you keep a home in the state and spend more than 183 days there during the year, you count as a statutory resident even if you claim domicile somewhere else. Those 183 days are counted in the aggregate across the year, not consecutively.1Justia. Delaware Code Title 30 – 1103 Resident Individual Defined
You’re a part-year resident if you moved into or out of Delaware during the year. You’re a nonresident if your home was outside Delaware for the entire year and you didn’t hit the 183-day test.
Income Thresholds for Full-Year Residents
If you’re a full-year resident, you must file when your individual Delaware adjusted gross income exceeds the threshold for your age and filing status. “Individual” is the operative word: this is your personal AGI, not a household total. The thresholds are based on gross income, before deductions. For the 2025 tax year (filed in 2026):2Delaware Division of Revenue. Delaware Individual Income Tax Return Resident Instructions
Single or Head of Household:
- Under 60: $9,400
- 60 to 64: $12,200
- 65 or older, or blind: $14,700
- 65 or older and blind: $17,200
Married Filing Jointly:
- Under 60: $15,450
- 60 to 64: $17,950
- 65 or older, or blind: $20,450
- 65 or older and blind: $22,950
Married Filing Separately:
- Under 60: $9,400
- 60 to 64: $12,200
- 65 or older, or blind: $14,700
- 65 or older and blind: $17,200
Claimed as a dependent on another person’s return:
- Under 60: $5,250
- 60 to 64: $5,250
- 65 or older, or blind: $7,750
- 65 or older and blind: $10,250
Fall below the line for your category and Delaware doesn’t require a return. Cross it, and you file Form PIT-RES.3Division of Revenue – State of Delaware. Personal Income Tax Forms
Nonresidents: Any Delaware Income Triggers Filing
If you’re a nonresident, the test is much stricter. Any gross income from Delaware sources during the year requires a return. There is no minimum dollar amount.2Delaware Division of Revenue. Delaware Individual Income Tax Return Resident Instructions Common examples of Delaware-sourced income include wages for work physically performed in the state, rent from Delaware real estate, and profits from a business operating there. Nonresidents file Form PIT-NON.
Delaware has no reciprocal tax agreements with any state.4Division of Revenue – State of Delaware. Withholding Tax FAQs If you live in Pennsylvania, New Jersey, or Maryland and commute to a Delaware job, you owe Delaware tax on those wages and will need to work out the double-taxation issue with your home state. Most neighboring states offer their own credit for taxes paid to Delaware, but check with your home state’s tax authority to confirm.
One narrow exception: if you’re married and your spouse files a separate return that reports Delaware-sourced income, but you personally had no Delaware income, you don’t need to file a Delaware return.5Delaware Division of Revenue. Delaware Non-Resident Individual Income Tax Return Instructions
Part-Year Residents
If you moved in or out of Delaware during the year, you generally file if you had any income while you lived in Delaware or any Delaware-sourced income during the part of the year you didn’t. Part-year filers use Form PIT-NON and report income earned during the resident period plus any Delaware-sourced income earned during the nonresident period.2Delaware Division of Revenue. Delaware Individual Income Tax Return Resident Instructions
Delaware gives part-year residents a choice in how to compute the tax. You can calculate it as if you were a resident for the entire year and claim the applicable credits, or as a nonresident while including all income from your resident portion of the year.6Delaware Code Online. Delaware Code Title 30, Chapter 11, Subchapter III Run both methods and pick the one that produces the lower tax.
Military Members and Their Spouses
If you’re an active-duty service member who is a nonresident of Delaware but stationed in the state, your military pay is not subject to Delaware tax. Where military pay is your only income, you generally don’t need to file a Delaware return. Any non-military Delaware income, like a part-time civilian job, would still be taxable and would trigger a filing obligation.
Under the Military Spouses Residency Relief Act, a spouse who relocates to Delaware solely to be with a service member stationed there can keep home-state residency for tax purposes. Wages earned in Delaware are reported on the home-state return instead. To stop Delaware withholding on your paycheck, file Form W-4DE with your employer.
File Anyway to Claim a Refund
Even if your income falls below the threshold, file a return if Delaware tax was withheld from your paychecks or you made estimated payments during the year. Filing is the only way to get that money back. Residents use PIT-RES; nonresidents and part-year filers use PIT-NON.
You have a limited window to claim a refund. Generally, that’s three years from the filing deadline of the original return, or two years from the date the tax was actually paid, whichever is later.7Justia. Delaware Code Title 30 – 539 Limitations on Credit or Refund If you file within the three-year window, your refund is limited to the tax paid during that three-year period plus any extension time. Miss both windows and the money stays with the state.
When the Return Is Due
Delaware’s individual income tax deadline is April 30, roughly two weeks after the federal due date. For the 2025 tax year, that’s April 30, 2026. When April 30 falls on a weekend or holiday, the deadline shifts to the next business day.
Need more time? File Form PIT-EXT by April 30 for an automatic extension to October 15.8Delaware Division of Revenue. Delaware Form PIT-EXT Application for Automatic Extension The extension buys you time to file, not time to pay. Estimate what you owe and send payment with the extension form to avoid penalties and interest. You can file electronically through the Delaware Taxpayer Portal at tax.delaware.gov or through approved third-party tax software.9Delaware Taxpayer Portal. Delaware Taxpayer Portal
What Happens If You Don’t File
Skipping a required return has two separate consequences that can stack. A late-filed return with a balance due carries a penalty of 5 percent per month on the unpaid amount.10Division of Revenue – State of Delaware. Personal Income Tax FAQs Failing to pay on time carries a separate penalty of 1 percent per month, capped at 25 percent of the net tax owed. A taxpayer who files late and pays late gets hit with both.
Unpaid balances also accrue interest at 0.5 percent per month from the original due date until paid in full, compounded monthly once the assessment becomes final.11Justia. Delaware Code Title 30 – 533 Interest on Underpayment No interest is charged if the total owed is less than one dollar. And if your tax after credits exceeds $800 and you didn’t pay enough through withholding or quarterly estimated payments, you may owe an additional underpayment penalty calculated at roughly 12 percent annually on the shortfall.