The Dutch tax return deadline (aangifte inkomstenbelasting)

According to the Belastingdienst, the Dutch Tax Administration, your return must be received before the date stated in your filing letter (aangiftebrief) — often 1 May. For the 2025 tax year, the standard deadline was 1 May 2026.

You can file online, with the app, or on paper. If you haven't filed yet and the deadline has passed, file as soon as possible to avoid a fine.

Sources: Belastingdienst — Wanneer moet mijn aangifte inkomstenbelasting binnen zijn?; Belastingdienst — Kan ik nog uitstel aanvragen?; both read 9 October 2026.

You can request an extension (uitstel) up to the date your return is due — for most people, until 1 May. If it's granted, you get 4 extra months to file.

The Belastingdienst warns that if you get an extension, you usually pay tax interest (belastingrente). If your return is due on a date other than 1 May, you can request the extension up to that date. If you use a tax adviser, they can arrange it for you.

Newcomers often have a more complex first return — part of the year abroad, part in the Netherlands, and perhaps the 30% ruling. Mark the date in your filing letter early, gather your annual income statements, and decide early whether you need an extension or an adviser.

You'll need your DigiD to file online and your BSN as your tax number — our guides explain both.