When you log in to MyTax, your tax-related letters will change from paper to electronic form automatically. Read more about the changes.
A self-employed person, business operator or business partnership: Report the real estate properties included in business assets.
Choose your filing method
Submit the information in MyTax as part of the tax return.
Other e-services:
Ilmoitin.fi (website for electronic transfer of files)
This is an enclosure form to Form 5 and Form 6A, the main tax returns.
If you file on paper, you can find the Tax Administration’s postal address on the form’s first page.
Download the form
Huomio osio alkaa
The online authorisation mandate
You can use the Suomi.fi Authorization to enable you to deal with taxes for another person – including legal persons, companies, other entities – through e-services, over the telephone, or by visiting a service point on their behalf.
Huomio osio päättyy
Huomio osio alkaa
Letters of authorisation on paper
You can receive a letter of authorisation written in the name of a company, to manage a single tax-related issue. If you – either personally or for an organisation that had been authorised – submit tax-related information on paper, a copy of the letter of authorisation has to be enclosed. A letter of authorisation does not provide access to MyTax.
Power of attorney for managing the taxes of a company (3804)
Huomio osio päättyy
Page last updated 6/23/2026