How to grant an authorisation for tax matters

You can authorise an agent to take care of your personal tax matters or your company’s taxes on your behalf. Your agent can be another person or a company, such as an accounting firm.

You can grant an authorisation on Companies can also use Katso authorisation up until the end of 2019.

Please note: Old Katso authorisations are not automatically replaced with new authorisations.

Two different authorisations

There are two different authorisations for tax matters:

An authorised agent can take care of all the tax matters of the person or company who has granted the authorisation. The agent can also access tax data in MyTax. For example, an accountant can be authorised to manage all the tax matters of a company.

The authorised agent can visit tax offices and call our telephone service as well as use MyTax,, and any future e-services on the authorising party’s behalf. However, the authorisation does not allow the agent to use or to submit reports to the Incomes Register. The Incomes Register requires separate authorisation.

The “Managing tax matters” authorisation can be used by

  • individual taxpayers
  • self-employed individuals
  • general and limited partnerships
  • limited companies, housing companies and cooperatives.

Agents can see the personal tax data of self-employed individuals

If you grant the “Managing tax matters” authorisation to an accounting firm, the firm can see your personal tax details as well as your company’s details in MyTax.

The agent can access the following details in MyTax:

  • income tax, inheritance tax, gift tax
  • advance rulings, claims for adjustment and decisions relating to income tax
  • decisions on claims for adjustment made by the Tax Administration and the Adjustment Board
  • letters and decisions concerning taxation
  • tax audit reports concerning business operations
  • decisions on advance rulings made in MyTax.

Inside information according to the EU regulation on market abuse is not available in MyTax. 

This authorisation allows the agent to file tax returns and other tax-related reports on behalf of the authorising party.

The agent can use and to file tax returns.

However, this authorisation does not allow the agent to use MyTax and access the authorising party’s tax data there.

How to grant an authorisation

See below for more detailed instructions specific to different company types.

You can authorise another person or company to take care of your tax matters on your behalf. You can grant the authorisation on Select the authorisation “Managing tax matters”.

Please note: After you have granted the authorisation, your agent can see, edit and file all your tax data in all Tax Administration service channels (MyTax, tax offices, telephone service). The agent can also change your bank account number in MyTax.

Managing the tax matters of an underaged child

If you have an underaged child, you are automatically authorised to take care of their tax matters in MyTax without an authorisation. The e-authorisation service checks the Population Information System to see if you have a guardian’s right to manage the child’s tax matters.

Authorisation granted in writing

If you have been granted a power of attorney on paper that authorises you to take care of another person’s taxes, you can ask an official at a tax office to create an authorisation for you on at the end of 2019. Present your power of attorney at the tax office. After this, you can use the MyTax e-service to take care of the other person’s taxes.

An agent can manage your tax matters on your behalf if you grant them the necessary authorisation.

  • Granting a new authorisation on
  • If you want to continue using Katso authorisations and your agent uses MyTax, you must activate the new Katso role “MyTax for individuals and entrepreneurs”.

Please note:

  • After the authorisation has been granted, the authorised agent can see, edit and file all of the authorising party’s tax details relating to their business operations and personal taxation. If you do not want your accountant or agent to see your personal tax data, do this:
    • Grant the “Filing tax returns” authorisation to your accountant on This authorisation allows the agent to file all necessary tax returns on your behalf.
    • Log in to MyTax with your personal e-bank codes, copy all the necessary details, and send them to your accountant.
  • Authorisation with a Business ID or personal ID: We recommend that authorisations are granted with a Business ID. If you grant an authorisation with your personal ID, the agent cannot see your data on the list of taxpayers in MyTax and they will not receive the monthly summary.

A self-employed individual can grant authorisations on even if they are not in the Trade Register.

If you take care of your company’s taxes and you have an official role recorded in the Trade Register, you can manage your company’s tax matters without authorisation. You can log in to the Tax Administration’s e-services with your personal e-bank codes.

If you want to authorise an agent to manage your company’s taxes, do this:

  • Create and grant a new authorisation on
    • Please note: The agent cannot change the company’s bank account number in MyTax. Only a representative of the company or cooperative, with an official role recorded in the Trade Register, can change the bank account number.
  • When you are using Katso authorisation: You can switch to a new authorisation or keep using Katso authorisation up until the end of 2019.

If you continue using Katso authorisation

Please change to authorisation well in advance before Katso authorisations are discontinued at the end of 2019. Note that you will only be able to use the following Katso roles:

  • Company’s Master User
  • Company’s Parallel Master User
  • Company MyTax

The following Katso roles have already been discontinued:

  • Company's income tax returns
  • Filer of self-assessed taxes.

More information about Katso authorisations

Agents authorised to manage the tax matters of any of these parties must use Katso identifiers and Katso authorisations in Tax Administration service channels for the time being. authorisations cannot be used for these tax matters.

Please note that the Katso roles “Company’s income tax returns” and “Filer of self-assessed taxes” can no longer be used to access MyTax as of 1 November 2018. Only the following Katso roles can access MyTax:

  • Company’s Master User
  • Company’s Parallel Master User
  • Company MyTax

Read more about Katso

Frequently asked questions

Two together signing for the company: At present, authorisations are not available for companies where two together are authorised to sign for the company. However, authorisations will soon be available for use in situations where two or more people must sign together.

One person’s limited company: You can grant an authorisation to your accountant on You can also manage your company’s tax matters yourself by logging in to MyTax with your personal identifier.

You must request a Katso authorisation from your new clients regardless of their company type. Direct access to Tax Administration services through Tyvi service channels still requires Katso authorisation. This will change during 2019. More details on when the change happens will be published soon. authorisations are only accepted in situations where the accounting firm does not have direct access to the Tax Administration from software, but instead uses MyTax for filing tax returns or uses to upload files generated by their accounting software.