How to claim adjustment to income taxes – corporate entities
This guide is for corporate taxpayers: limited-liability companies (Oy, Ab), cooperative societies, associations, foundations.
You can make a claim for adjustment as soon as the tax assessment process has ended. When the assessment process is still ongoing, you can submit a new tax return before the end date of assessment in order to make any necessary adjustments or changes. Submit a claim of adjustment to the Assessment Adjustment Board.
Those who may appeal decisions are the taxpayers themselves, any others whose taxes may be affected, and those responsible for paying the tax. For example, after a corporate merger is carried out, the receiving company can appeal against the income taxation of the company that merged into the receiving company. A parent company, however, is not allowed to appeal against the taxes imposed on its subsidiary companies.
When can a claim for adjustment be submitted?
You can claim adjustment within 3 years of the start of the calendar year following the end of the tax year. Instructions for appeal are enclosed with the tax decision your company received; read them to check the deadlines.
You can claim adjustment as soon as the tax assessment process has ended. The end date is stated in the tax decision. However, the end date is never later than 10 months from the end of the company’s accounting period. When the assessment process is still ongoing, you can submit a new tax return before the end date of assessment in order to make any necessary adjustments or changes.
For the majority of companies and other corporate entities, the tax year is the same as the calendar year. The exception to this are the corporate entities with a non-calendar accounting year. Then the tax year is the accounting year, accounting period or periods that closed during the calendar year.
Example: The accounting year of a limited-liability company is 1 July 2019 to 30 June 2020. To file a claim for adjustment of corporate income taxes for the 2020 tax year, the deadline is 31 December 2023. The claim must arrive at the Tax Administration on that date.
When the end date of the calendar year falls on a Saturday or Sunday, the deadline is the next business day. The claim for adjustment must arrive at the Tax Administration by 4.15 pm.
How to claim adjustment
Claim for income tax adjustment in MyTax.
- After logging in to MyTax, go to the ‘Activities’ tab.
- Under ‘Claims for adjustment’, open ‘All adjustment matters’.
- Select ‘Make a claim for adjustment of corporate income tax’.
- Go to the appropriate year and click ‘Claim for adjustment’.
If you do not have access to MyTax: Use the provided paper form or a free-form application to make the claim.
After claiming for adjustment
If you have an unpaid back tax, pay the tax by its due date even if you have claimed adjustment. If necessary, you can request a payment arrangement or an order preventing enforcement.
After your claim for adjustment is processed, you will be sent a decision on the matter in MyTax and to your home address by mail. The decision has all the information on possible tax refunds or back taxes. Check the estimate on the processing time