Delaware State Tax Guide
Click your state on the map to see filing deadlines, extension rules, refund tracking, and payment options for that state. States shown in gray are coming soon.
Hover or tab a state to see its name.
Delaware State Tax Guide
Extension rules
Extension type: Separate State Tax Ext Required · Form PIT-EXT (Application for Automatic Extension)
If you requested a Federal Extension (Form 4868) AND owe $0 in Delaware taxes: You do not need to file a separate state extension form. Delaware automatically honors your federal extension. If you owe Delaware state taxes: You must file a state extension form and submit your payment by the April 30 deadline to avoid penalties and interest. If you owe Delaware income tax, you must file Form PIT-EXT (Application for Automatic Extension of Time to File a Delaware Individual Income Tax Return) by April 30, 2026. This form must be accompanied by full payment of any taxes owed. If no taxes are due and you have a valid federal extension, Form PIT-EXT is not required—the extension is granted automatically.
If you owe tax: If you owe Delaware state taxes: You must file a state extension form and submit your payment by the April 30 deadline to avoid penalties and interest. If you owe Delaware income tax, you must file Form PIT-EXT (Application for Automatic Extension of Time to File a Delaware Individual Income Tax Return) by April 30, 2026. This form must be accompanied by full payment of any taxes owed.
If you owe $0: If you requested a Federal Extension (Form 4868) AND owe $0 in Delaware taxes: You do not need to file a separate state extension form. Delaware automatically honors your federal extension. If no taxes are due and you have a valid federal extension, Form PIT-EXT is not required—the extension is granted automatically.
How to request
- Online: Electronic Filing (Recommended): You can file your extension and pay any balance electronically via the state's portal: Delaware tax portal
- Mail: Paper Form: If you prefer to mail a physical form with a check, you must use Form PIT-EXT (Application for Automatic Extension). You can download it directly from the Delaware personal income tax forms
Any tax owed is still due by the original filing deadline of April 30. If you owe tax and do not pay by April 30: • Interest begins accruing immediately. • Additional penalties may also apply.
Relevant Links
Delaware Key deadlines (tax year 2025, return filed in 2026)
- Filing deadline: Apr 30, 2026
- Extension request deadline: Apr 30, 2026 — Extension Request & Payment Due Date: April 30 (Delaware has a unique statutory deadline that is later than the federal deadline).
- Extended return deadline: Oct 15, 2026 (6-month extension)
- Payment deadline: Apr 30, 2026
- Differs from federal: Yes — Extension Request & Payment Due Date: April 30 (Delaware has a unique statutory deadline that is later than the federal deadline).
Any tax owed is still due by the original filing deadline of April 30. If you owe tax and do not pay by April 30: • Interest begins accruing immediately. • Additional penalties may also apply.
Extended Filing Deadline: October 15. An approved extension gives you an extra 5.5 months to submit your completed tax return.
Payment rules
Failure-to-Pay Penalty: If you don't pay by the deadline, Delaware charges a penalty of 1% per month of the outstanding balance (up to a maximum of 25%), plus an interest charge of 0.5% per month until it's paid in full. Failure-to-File Penalty: If you don't file your return or extension on time, the penalty is a steep 5% per month of the unpaid tax, up to 50%.
Official payment portal
Payment options
Payment plan availability
Available: Yes
Short-Term & Long-Term Agreements: Delaware allows individual installment agreements to pay off tax debt. Short-term plans (under 180 days) are easier to set up and usually don't carry a setup fee. Long-term plans (over 24 months) typically require automatic monthly bank withdrawals to prevent a tax lien from being filed. How to Apply: Once you receive a formal tax bill or notice, you can set up an agreement by calling the Delaware Division of Revenue Installment Section directly at (302) 577-8586 or by reviewing the Pay your bill / collections. You may be asked to fill out a Collection Information Statement to verify your financial hardship.
Relevant Links
Filing forms
Extension
- Form PIT-EXT - Application for Automatic Extension of Time to File a Delaware Individual Income Tax Return
Delaware Refund Tracking
Processing time: Go to Delaware check refund status
Do I need to file?
If you requested a Federal Extension (Form 4868) AND owe $0 in Delaware taxes: You do not need to file a separate state extension form. Delaware automatically honors your federal extension. If you owe Delaware state taxes: You must file a state extension form and submit your payment by the April 30 deadline to avoid penalties and interest.
- Residents: If you requested a Federal Extension (Form 4868) AND owe $0 in Delaware taxes: You do not need to file a separate state extension form. Delaware automatically honors your federal extension.
- Part-year residents: If you owe Delaware state taxes: You must file a state extension form and submit your payment by the April 30 deadline to avoid penalties and interest.
- Nonresidents: If you owe Delaware state taxes: You must file a state extension form and submit your payment by the April 30 deadline to avoid penalties and interest.
Filing methods
Online filing
Electronic Filing (Recommended): You can file your extension and pay any balance electronically via the state's portal: Delaware tax portal
Mail filing
Paper Form: If you prefer to mail a physical form with a check, you must use Form PIT-EXT (Application for Automatic Extension). You can download it directly from the Delaware personal income tax forms
