MyTax is the Tax Administration’s e-service for most of your tax matters. You can log in with your online banking codes, a mobile certificate, or a Katso ID. If you wish to act on behalf of someone else, you will need authorisation.
How to make a tax card
How to file a tax return - corporate taxpayer
MyTax instructions for individual and corporate taxpayers
How do I find the correct reference number in MyTax?
When do I need a new tax card?
Why have I not received my tax refund?
What does it mean that my tax refund is used for paying my taxes?
Where can I find the tax decision in MyTax?