Why do expats get refunds?
When you work in the Netherlands, your employer withholds income tax calculated as if you worked the full year. If you only worked part of the year, you have been overtaxed. The M-form (Migratie) is for people who moved to or from the Netherlands during the year.
How far back can I claim?
Up to 5 years back. In 2026 you can still file for 2021, 2022, 2023, 2024.
Documents needed
Jaaropgave (annual income statement from employer)
BSN and Dutch IBAN
If you worked abroad: foreign income certificate