
As the 2026 tax season progresses, Delaware residents and business owners are reminded of important filing and payment deadlines — and why some taxpayers may experience delays in receiving refunds.
Delaware’s Division of Revenue began processing individual income tax returns for the 2025 tax year on January 26, 2026. The deadline to file and pay state personal income tax is Thursday, April 30, 2026. This is later than the federal deadline of April 15, 2026, meaning many taxpayers will face two key dates this spring.
While many expect refunds soon after filing, Delaware is known for delaying state refunds more than in some other states. According to state tax officials, these delays often result from increased fraud prevention measures, identity verification procedures, and programming that checks returns against federal IRS data to ensure accuracy. These steps help protect taxpayers from identity theft and erroneous refunds, but they can extend processing times.
“Delaware’s additional safeguards are designed to protect taxpayer dollars, but they may result in longer wait times for some refunds compared with prior years,” a spokesperson for the Division of Revenue said.
Business entities face varying deadlines. S corporations and partnerships generally must file by March 16, 2026, while C corporations typically have an April 15, 2026, deadline. Delaware corporations must file their annual report and franchise tax by March 1, 2026, while LLCs and similar entities must pay theirs by June 1, 2026.
Taxpayers planning extensions should remember that extensions apply only to filing — not to paying taxes owed. Any tax due must be paid by the original deadline or penalties and interest may apply.
Delaware officials encourage electronic filing and direct deposit to help speed the process and minimize refund delays.

