I lived partly outside the Netherlands in 2020 - how do I file a tax return?
You have to file an M tax return if you lived in the Netherlands for part of the year, because you have emigrated from the Netherlands or have immigrated to the Netherlands.
You can file your 2020 M tax return online
Until 1 June you could only file your 2020 M tax return on paper (in hard copy)
You can request an M Form online.
File your tax return before 1 July
Then your tax return is on time. Or apply for a postponement well in advance. If we receive your tax return after 1 May, you may have to pay tax interest (Dutch).