Claim for adjustment of income tax
This guidance is for individual taxpayers, self-employed business operators, and agricultural and forestry operators.
If you need to make additions or corrections to the pre-completed tax return you received in Spring 2021, you can submit the changes in MyTax or on paper forms. How to make corrections in MyTax or on paper
If you notice something that must be changed after your tax assessment has ended, you must file a claim for adjustment to the Tax Administration’s Adjustment Board. For many individual taxpayers, the assessment for 2020 ends as early as late May 2021.
If you are filing additional information late but your tax assessment has not ended yet, see the instructions here.
Everyone has their own personal end date for the tax assessment process. As a rule, the assessment is completed in the time between July and October of the year following the tax year. You can see the end date for your tax assessment on MyTax or on your tax decision. The assessment of spouses always ends at the same time.
Please note that the end date of your assessment may be postponed if you or your spouse make changes to your pre-completed tax returns or if the Tax Administration receives some other information that affects your assessment. In this case, you will receive a new tax decision containing a new assessment end date.
The tax assessment process for tax year 2017 ended on 31 October 2018 for all taxpayers. In previous years, the end date of the tax year’s assessment process was always 31 October in the following year.
Taija receives her pre-completed tax return for 2020 in the spring of 2021. She must file any changes to the tax return by 11 May 2021. The details on the tax return seem to be correct, so she does not make any changes to them.
However, Taija notices later that there is a mistake in her commuting expenses. The pre-completed tax return includes a tax decision which states that the end date of Taija’s tax assessment is 18 June 2021.
If Taija notices the mistake before the end date, she can correct it by filing new details in MyTax or on the travel expense form 1A. If Taija notices the mistake only after the assessment has ended on 18 June, she can file a claim for adjustment in MyTax or on the paper form “Claim for adjustment of income tax”.
How to file a claim for adjustment?
You can file a claim for adjustment electronically in MyTax. Full contents of the tax decisions are available in MyTax starting with tax year 2018. For 2015–2017 tax decisions, you can only see some identifying details (decision dates, decision numbers, types of taxes) in MyTax.
You can also make the claim on paper by filing a Claim for adjustment of income tax (Form 3308e on paper) or by writing a free-form claim.
What details must be included in the claim for adjustment?
A claim for adjustment must always indicate
- the name and personal ID of the person making the claim
- the tax year that the adjustment concerns
- the changes that you claim
- the grounds for these changes
Enclose any relevant documents that support your claim, unless you have already sent them to the Tax Administration. If you wish that the decision is sent to your representative, please say so on your claim and give the representative’s address.
When must the claim for adjustment be filed?
You can make a claim for adjustment as soon as the tax assessment process has ended. Until the end date of your tax assessment, you can still make additions and corrections to your income tax return in MyTax or you can complete and submit separate paper forms to add or correct something.
Claims for adjustment against income taxes can be made within 3 years from the beginning of the calendar year following the tax year.
If your claim concerns tax years 2015–2016, you must file it within 5 years from the beginning of the calendar year following the tax year in question.
Check the tax year and read the instructions for appeal that are enclosed with your tax decision.
If the last day of the calendar year is a Saturday or Sunday, the deadline for the claim is extended to the next business day. Note: both for paper filing and electronic filing in MyTax, it is required that claims for adjustment arrive at the Tax Administration by 4:15 pm on the appeal period’s last day.
|Tax year||Deadline when the claim must be at the Adjustment Board|
|2014||Appeal period has expired 31 December 2020|
|2015||31 December 2021|
|2016||2 January 2023|
|2017||31 December 2020|
|2018||31 December 2021|
|2019||2 January 2023|
|2020||2 January 2024|
|2020||31 December 2024|
The appeal period may be shorter if the adjustment decision is initiated by the Tax Administration
Your tax assessment may be adjusted by the Tax Administration, if the Tax Administration receives information that affects your taxes after the assessment process has ended. You can appeal an adjustment decision made by the Tax Administration by filing a claim for adjustment to the Adjustment Board.
Remember to check the length of the appeal period in the instructions enclosed with the decision. The appeal period is either 3 or 5 years, depending on whether the decision was made before or after 1 January 2017.
Read more about adjustment decisions by the Tax Administration and about appealing them (available in Finnish and Swedish, link to Finnish).
If you include new information in your claim for adjustment
If you provide some completely new information in your claim for adjustment, the Tax Administration will assess it and make a supplementary tax decision. This information may be a new item of income, a new deduction, or other relevant information that had not been included in your tax return or had otherwise not been accounted for in your tax decision.
Starting with tax year 2018, a new procedure for supplementary tax decisions is applied. You can appeal a supplementary tax decision by filing a claim for adjustment with the Adjustment Board. The appeal period is the same as for original tax decisions. The appeal period is stated in the instructions for appeal enclosed with the supplementary tax decision.
Only claims submitted within the appeal period will be considered
You must make your claims for adjustment to the Tax Administration before the appeal period ends. Remember to allow enough time for postal delivery to ensure that your documents have arrived at the Tax Administration by the last day of the appeal period. It is required that claims for adjustment arrive at the Tax Administration by 4:15 pm on the appeal period’s last day. Claims that arrive after the appeal period has ended will not be considered.
Taxes must be paid even if an appeal is pending
You must pay your taxes by their original due dates. If you leave a tax unpaid, it will collect interest, even if you have made a claim for adjustment for it. However, you may request the Tax Administration to prevent or postpone any recovery of tax by enforcement while your claim is being processed. Read more about interruption of enforced recovery. If the recovery of the tax is prevented of postponed, the original overdue amount will continue to accrue late-payment interest as normal.
Appeals to the Administrative Court and Supreme Administrative Court
If you disagree with the Adjustment Board's decision and wish to make a further appeal, you must do so to the Administrative Court.
- The appeal period is 60 days from the date when you received notice of the Adjustment Board's decision.
- Appeals concerning tax years 2015–2016 must be filed within 5 years from the beginning of the calendar year following the end of the tax year’s assessment. If your appeal concerns a tax adjustment decision initiated by the Tax Administration and dated 1 January 2017 or later, the period of appeal to the Administrative Court is 60 days from the date when you received notice of the Adjustment Board’s decision.
- Always check the length of the appeal period from the instructions enclosed with the decision.
Appeals must be delivered to the Administrative Court by the end of the appeal period. They must arrive no later than 4:15 pm on the appeal period’s last day.
- You can also file an appeal in the e-service of the Administrative and Special Courts (available in Finnish and Swedish, link to Finnish).
- Check the addresses of Administrative Courts (www.oikeus.fi).
If you disagree with the ruling of the Administrative Court, you can appeal to the Supreme Administrative Court, if the Supreme Administrative Court gives you permission to do so. Appeals must be submitted within 60 days from notice of the Administrative Court’s ruling.
Appeals to the Administrative Court or Supreme Administrative Court may be subject to a charge.
More information on the fees charged by courts of law (www.oikeus.fi).
ple 1: The assessment of taxes for individual taxpayers was completed 31 October 2016. Claims of adjustment with regard to tax year 2015 must arrive at the Tax Administration by 31 December 2021.
Example 2: Claims of adjustment with regard to tax year 2017 must arrive at the Tax Administration by 31 December 2020.
Example 3: The Tax Administration adjusted your 2014 taxes on its initiative on 15 January 2017. You have time to file a claim of adjustment regarding this decision by 31 December 2017.
Example 4: The Tax Administration adjusted your 2013 taxes on its initiative on 22 March 2017. You have 60 days to file a claim of adjustment regarding this decision, counting from the date when you received notice of it.
Example 1: The assessment of taxes for individual taxpayers was completed 31 October 2017. Claims of adjustment with regard to tax year 2016 must arrive at the Tax Administration by 2 January 2023.
Example 2: Claims of adjustment with regard to tax year 2018 must arrive at the Tax Administration by 31 December 2021.
Example 3: Claims for adjustment with regard to tax year 2019 must arrive at the Tax Administration by 2 January 2023. The date when the Tax Administration finishes your personal income-tax assessment has no effect because the appeal period’s start only depends on the end date of the tax year.
Example 4: The Tax Administration adjusted your 2018 taxes on its initiative on 14 June 2020. You have time to file a claim of adjustment regarding this decision by 31 December 2021.
Example 5: The Tax Administration adjusted your 2016 taxes on its initiative on 22 March 2021. You have 60 days to file a claim of adjustment regarding this decision, counting from the date when you received notice of it.
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