Anyone filing a tax return in Switzerland is not immune to errors. If you have the tax return prepared by a tax advisor, you reduce the risk, but errors are still not excluded. If you have noticed that you have made a mistake, you can submit the changes to your cantonal tax administration retrospectively. However, you also have the option of filing an objection if you have already received your tax assessment.
Risk of losses in the event of errors in the tax return
If you make a mistake when filing your tax return, it can have serious financial consequences. Often the tax administration does not notice such errors and consequently does not correct them. As a taxpayer, you therefore often miss out on large amounts that are either not refunded to you or that you have to pay in arrears. Errors can also lead to the tax administration accusing you of fraud or tax evasion and imposing a hefty fine on you.
If the tax administration has not yet made an assessment, you can correct the error retrospectively to avoid serious consequences. If you do not make a correction after filing your tax return, you can still wait for the assessment. Once you have been served with the assessment, you should act quickly. Check the assessment and make any necessary correction in the short term.
If you miss the deadline of 30 days set by the tax administration, it is difficult to still correct errors.
Only under strict conditions is there the possibility of an appeal, but this is rarely promising.
Correct tax return retrospectively – how to proceed?
If you have already submitted your tax return to the cantonal tax administration and noticed an error, you can make the correction if you have not yet received an assessment notice. They should be as fast as possible. A tax advisor can help you. Let him know what mistake you have made. The tax advisor writes a letter to the cantonal tax administration and informs about the error. He sets the record straight. External tax assistance is worthwhile in most cases.
Of course, you can make the subsequent correction without a tax advisor. Write a letter to the cantonal tax administration stating your contact and tax data. Inform about the desired changes and ask the cantonal tax administration to make the changes for you. Attach the required documents to your letter if they are still available. Otherwise, refer to the documents already submitted. If you have a copy of such documents, they can be submitted instead of the originals.
You do not have to expect any fees or penalties if you make a subsequent correction and have not yet received the assessment certificate.
Retroactive correction after receipt of the assessment certificate
Once you have received your assessment certificate, the cantonal tax administration grants you a period of 30 days to examine it. If you find errors, you can file an objection within this time. This is also completely free of charge and does not involve any consequences for you.
Write a letter to the cantonal tax administration and refer to the assessment certificate. Specify the appropriate data. The objection must always be in writing and signed by you. An objection by e-mail or fax will not be recognized, as it does not contain an original signature. Justify the errors identified in your appeal and submit supporting documentation. Copies of invoices, photographs, bank statements, federal court judgments or bank records will be accepted as evidence.
Even after receiving the assessment certificate, you can hire a tax advisor to file an appeal. He sends a corresponding letter to the tax administration and lists the errors in it. However, this is associated with costs for you, as the tax advisor charges a fee for his work. Read more about the cost of a tax advisor here.
The more detailed and meaningful the objection is, the better the chances of getting the overpaid money refunded. However, an appeal can also be made if you have to pay more than specified. In this case, you will avoid a large additional payment in the event of an audit by the tax authorities, which is associated with a fine.
Deadline missed for assessment certificate – what then?
If you have missed the deadline of 30 days after receiving the tax assessment to make a correction, it becomes difficult. In this case, you should consult a tax advisor who can still appeal. However, strict conditions apply to the revision. Errors must be carefully justified. A revision is subject to a fee. The costs you will incur depend on the specific case and the respective canton.
Objection rejected – that is your right
If you have filed an objection to the tax assessment within the time limit and your objection has been rejected, you can appeal the objection decision within 30 days. You must apply in writing to your competent cantonal court. In any case, you should consult a tax advisor, because if you are defeated in the cantonal court, you will have to bear the costs.
Other ways to correct errors on the tax
There are several other cases in Swiss income tax where you can make an adjustment. If you have not met any deadlines when filing your tax return and the tax administration has sent you a discretionary decision, you can file an appeal and submit a tax return within 30 days.
Spelling or clerical errors can also lead to incorrect decisions by the tax administration. You may correct such errors within five years of a final order.
If you have not declared income or assets in your tax return, there is the possibility of a penalty-free voluntary disclosure. This is still possible retroactively for up to ten years, regardless of whether you intentionally or unintentionally failed to declare income or assets.
You will then still receive a tax assessment and will have to pay the unpaid taxes in arrears. With the penalty-free voluntary disclosure you avoid a high fine due to tax evasion.