Yes, you probably have to file a Delaware state tax return if you lived in Delaware and your income crossed a threshold set by your age and filing status, or if you earned any income from a Delaware source while living somewhere else. Delaware residents under 60 filing single must file once income tops $9,400; married couples filing jointly under 60 must file above $15,450. Nonresidents face a stricter test with no dollar floor at all: any Delaware-sourced income triggers a return.
Which Kind of Delaware Filer You Are
Delaware splits individual taxpayers into three groups, and the group you fall into decides whether and how you file.
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 a temporary absence, not simply where you spent the 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’re a statutory resident even when you claim your legal home is elsewhere. Those days do not have to be consecutive; they’re added up across the full year.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 report income earned while you lived in Delaware plus any Delaware-sourced income earned during the part of the year you lived elsewhere.2Delaware Division of Revenue. Delaware Individual Income Tax Return Resident Instructions Delaware lets part-year residents choose: compute tax as a full-year resident and claim applicable credits, or compute as a nonresident while still including all income from the resident portion of the year.3Delaware Code Online. Delaware Code Title 30, Chapter 11, Subchapter III
You’re a nonresident if your home was outside Delaware for the full year and you didn’t trip the 183-day statutory residency rule.
Income Thresholds for Delaware Residents
If you’re a full-year resident, you must file when your individual Delaware adjusted gross income exceeds the threshold matching your age and filing status. The word “individual” matters here. This is your personal AGI, not a household total. For the 2025 tax year, filed in 2026, the thresholds are: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
These are gross-income triggers, measured before deductions. Fall below the line and Delaware doesn’t require a return. You may still want to file one if tax was withheld from your paychecks, which is covered further down.
The Nonresident Rule: Any Delaware-Source Income
Nonresidents face a much simpler and much stricter test. If you had any gross income from a Delaware source during the year, you must file. There is no minimum dollar amount.2Delaware Division of Revenue. Delaware Individual Income Tax Return Resident Instructions Common examples are wages for work physically performed in Delaware, rent from a Delaware property, and profits from a business operating in the state.
One narrow exception: if you’re married and your spouse files a separate return reporting Delaware-sourced income, but you personally had none, you do not need to file a Delaware return of your own.4Delaware Division of Revenue. Delaware Non-Resident Individual Income Tax Return Instructions
Delaware has no reciprocal tax agreements with any state.5Division of Revenue – State of Delaware. Withholding Tax FAQs If you live in Pennsylvania, New Jersey, or Maryland and commute to a job in Delaware, you owe Delaware tax on those wages and have to work out double taxation with your home state. Most neighboring states give their own residents a credit for tax paid to Delaware, but confirm that with your home state’s tax authority.
Military Members and Military Spouses
Federal law shifts the answer for service 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, and you generally don’t need to file a Delaware return if military pay is your only income. Non-military income earned in Delaware, like a part-time civilian job, would still be taxable there.
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 the spouse earns in Delaware are reported on the home-state return instead. To stop Delaware withholding from being taken out of your paycheck, file Form W-4DE with your employer.
When to File Even if You’re Not Required To
File anyway if Delaware income tax was withheld from your paychecks or you made estimated payments during the year. That’s the only way to get the money back. Residents use Form PIT-RES; nonresidents and part-year filers use Form PIT-NON.6Division of Revenue – State of Delaware. Personal Income Tax Forms
Don’t wait too long. You generally have three years from the filing deadline of the original return, or two years from when the tax was actually paid, whichever is later.7Justia. Delaware Code Title 30 – 539 Limitations on Credit or Refund File within the three-year window and your refund is capped at the tax paid during that three-year period plus any extension time. Miss both deadlines and the money stays with the state.
When Delaware Returns Are Due
Delaware’s individual income tax deadline is April 30, roughly two weeks later than the federal due date. For the 2025 tax year, that’s April 30, 2026. If April 30 lands on a weekend or holiday, the deadline moves to the next business day.
Need more time? You can get an automatic extension to October 15, 2026 by filing Form PIT-EXT on or before April 30.8Delaware Division of Revenue. Delaware Form PIT-EXT Application for Automatic Extension The extension buys time to file, not time to pay. Estimate what you owe and send it with the extension form to keep penalties and interest from piling up.
Returns can be filed electronically through the Delaware Taxpayer Portal at tax.delaware.gov or through approved tax software.9Delaware Taxpayer Portal. Delaware Taxpayer Portal Paper filings are accepted when postmarked by the deadline.
What Happens If You Skip a Required Return
Two penalties can hit at once. A late-filed return with a balance due is penalized at 5 percent per month on the unpaid amount.10Division of Revenue – State of Delaware. Personal Income Tax FAQs A separate late-payment penalty runs at 1 percent per month, capped at 25 percent of the net tax owed. They run independently, so filing late and paying late draws both.
Interest accrues on top at 0.5 percent per month from the original due date until the balance is paid in full and compounds 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.
Delaware also penalizes underpayment of estimated taxes. If your liability after credits tops $800 and your withholding or quarterly payments fell short, an additional penalty of roughly 12 percent annually applies to the shortfall. Covering at least your full prior-year liability through withholding or estimates is the usual way to stay clear of it.