A Swiss VAT error is not always an arithmetic mistake. It may start with late registration, an incorrect accounting code or a foreign supplier’s invoice treated as a Swiss invoice. When the underlying settings are wrong, the same error can repeat for months.
Here are the checks that matter and the steps for correcting a VAT return. The aim is to restore accurate figures and keep a clear record of what changed.
At a glance
- Check the registration threshold against the relevant turnover, not your profit.
- You cannot simply multiply a VAT-inclusive price by 8.1% to extract the VAT.
- The effective method and the net tax rate method do not treat input VAT in the same way.
- A foreign supplier’s invoice may trigger acquisition tax. The absence of Swiss VAT on the invoice does not settle the question.
- Correct a reporting-period error through the corresponding amended return. Annual reconciliation is a separate procedure.
Read feedback from entrepreneurs supported by Entreprendre.ch.
1. Waiting too long to check whether you must register
The ordinary CHF 100,000 threshold concerns relevant worldwide turnover. A business can make a loss and still be required to register. A new company with substantial contracts already in place must assess its forecast turnover over twelve months.
Identify supplies exempt without input tax credit. The special CHF 250,000 threshold applies only to certain qualifying associations and institutions, not to every non-profit organisation.
How to correct it: collect turnover figures by supply type and period, then establish the correct registration date. Late registration can result in VAT becoming payable on sales already invoiced. Whether you can recover that VAT from your customer also depends on the contract; it is not guaranteed.
Our Swiss VAT registration article explains this initial assessment.
2. Using the wrong VAT rate
The current Swiss rates are 8.1% at the standard rate, 2.6% at the reduced rate and 3.8% for qualifying accommodation. The applicable rate depends on the supply. The reduced rate is not a discount you can choose for a small customer.
Activities involving several elements, such as a product sale and a service, require correct classification. Rate changes must also be linked to the relevant period of supply, not automatically to the date printed on the invoice.
How to correct it: check your product catalogue and VAT codes, identify every affected transaction and amend invoices where necessary. Changing the software rate for future sales alone leaves the earlier incorrect returns unresolved.
3. Confusing VAT-exclusive, VAT-inclusive and “net” prices
A CHF 1,000 VAT-exclusive price at the standard rate gives CHF 81 of VAT and a total of CHF 1,081. To extract VAT from a CHF 1,000 VAT-inclusive price, calculate 1,000 × 8.1 ÷ 108.1 = CHF 74.93. The VAT-exclusive amount is CHF 925.07.
Depending on the document, “net price” may mean after a discount or excluding VAT. The phrase alone does not tell you whether VAT is included. A quotation should state this clearly.
How to correct it: check your sales terms and Swiss invoice templates, then recalculate from the correct base. If you promised the customer a total price, you may need to absorb the VAT within that amount. Use the worked explanations in our Swiss VAT article to check your calculations.
4. Deducting input VAT you are not entitled to recover
A cost paid with the company card is not automatically a business expense. Private use, exempt supplies without input tax credit and mixed activities can restrict deductions or require adjustments.
Invoices and other supporting records must substantiate the supply and its VAT treatment. A formal defect does not always mean a permanent loss of the deduction, but it should not be ignored. Foreign VAT does not become Swiss input VAT merely because it appears on an invoice.
How to correct it: obtain missing records, check the supplier and allocate purchases according to their actual use. For a company vehicle, assess the private-use adjustment. To identify a supplier, use the VAT number and register checks.
5. Mixing the effective and net tax rate methods
Under the effective method, you deduct eligible input VAT from the VAT calculated on your sales. Under the net tax rate method, the authorised rate applies to VAT-inclusive turnover and incorporates a standardised allowance for input tax.
A common mistake is to apply that rate to VAT-exclusive revenue and then also deduct the actual VAT on purchases. This combines two incompatible treatments. Another error is to show your net tax rate on a customer invoice instead of the statutory rate for the supply.
How to correct it: return to the method authorised by the FTA and reconstruct the return using the correct base. Check the conditions before changing methods: you cannot freely backdate a more favourable choice.
6. Overlooking cross-border transactions
Software subscriptions, advertising campaigns and consultancy purchased abroad may require an acquisition tax assessment. The supplier may invoice without Swiss VAT even though the Swiss customer has a tax obligation.
A VAT-registered business must declare acquisitions covered by this mechanism without applying the CHF 10,000 threshold. Under the effective method, any corresponding deduction depends on its input tax entitlement. For a recipient that is not VAT-registered, the obligation arises when the relevant acquisitions exceed CHF 10,000 in a calendar year. The tax then applies to all those acquisitions, not just the amount above the threshold.
Example: a small Swiss business that is not VAT-registered purchases CHF 12,000 of taxable consultancy during the calendar year from a foreign supplier that is not registered for Swiss VAT. If the services fall under the recipient-location rule and the standard rate, it must declare CHF 12,000 × 8.1% = CHF 972, not CHF 162 on just the CHF 2,000 excess. In this situation, it cannot recover that amount as input VAT. It must notify the FTA and declare the acquisitions within 60 days after the end of the calendar year.
Not every foreign invoice falls under this mechanism. Imports of goods, supplies located abroad and certain electronic services to non-registered recipients follow different rules. A description such as “software” or “advertising” is not enough on its own. See the FTA’s acquisition tax explanation and its VAT brochure, chapter 6 (in French).
How to correct it: review your foreign supplier list, classify the transactions and reconcile imports with customs records. Equally, a customer being outside Switzerland does not automatically make all your own sales VAT-exempt.
7. Reporting in the wrong period or missing a correction
Reporting follows agreed or collected consideration, according to the authorised basis. Mixing issued invoices with cash receipts can move turnover into the wrong period or count it twice. Credit notes, cancellations and adjustments need consistent treatment.
How to correct it: for an error in a specific return, use the correction for that reporting period in the FTA portal. This also applies to an annual return, for which the FTA provides an amendment procedure. Do not confuse this with annual reconciliation under article 72 of the VAT Act. Do not simply put an old amount into the current period to make the bank balance “work”. See the amended VAT return procedure and the annual return information.
Prepare a note explaining the error, affected invoices, original period and corrected amounts. This provides a clear audit trail for the year-end close or a tax inspection.
8. Neglecting deadlines, reconciliation and supporting records
The return and payment are generally due within 60 days after the end of the applicable reporting period. Do not assume that an extension for filing automatically extends the payment deadline.
Annual reconciliation compares the accounts with the returns submitted. Adjustments identified through this check are reported on the annual reconciliation form under article 72 of the VAT Act. Only the differences are declared. The FTA generally treats the returns as finalised if it receives no correction within 240 days after the financial year-end; this does not prevent audits or erase mistakes.
How to correct it: reconcile turnover, VAT accounts, input tax and special transactions. If the reconciliation reveals no differences, no annual reconciliation adjustment needs to be filed. Late corrections may trigger interest; the rate for the relevant claims is 4% in 2026 and must be checked for each year.
Retain books and supporting documents for the statutory period, generally ten years, and longer for certain property-related VAT records. Documents must remain legible and traceable to the accounting entries.
Frequently asked questions
Can I correct a mistake in my next VAT return?
For an error relating to a period already reported, amend that period’s return. Annual reconciliation has a specific procedure for differences identified at year-end.
Does annual reconciliation replace periodic returns?
No. It checks consistency between your returns and accounts. It is not the same as authorisation to file VAT returns annually.
Above CHF 10,000 of acquisitions, is only the excess taxed?
No. For a non-VAT-registered recipient that exceeds the annual threshold through relevant acquisitions, the tax applies to all those acquisitions, not just the excess. The threshold does not operate in the same way for a business already registered for VAT.
Sources and updates
- FTA: annual VAT reporting since 2025.
- FTA: principles of value added tax (in French).
- FTA: acquisition tax.
- FTA: annual reconciliation.
- FTA: amended VAT returns.
- FTA: tax liability and acquisitions.
- FTA: paying VAT.
- FTA: interest rates for 2026 (in French).
English editorial review: 22 September 2026. Tax information follows the French article’s documentary review of 20 September 2026.
Romain Prieur is a Swiss-qualified chartered accountant and the founder of Entreprendre.ch. With more than ten years of experience in audit and business advisory in Switzerland, he helps entrepreneurs with company formation, accounting and business taxation.
Fix the cause, then correct the returns
Start by defining the affected periods and invoices. Correct the underlying software settings, then the relevant documents and returns. Finally, reconcile the adjustment with the expected payment or refund. An internal accounting adjustment does not, by itself, submit a correction to the FTA.
Since 2025, eligible businesses can apply for annual VAT reporting subject to conditions. This removes neither the need to track transactions nor the obligation to make advance payments. Use the FTA’s current portal: old “VAT Return easy” tutorials no longer describe the available service.
If several financial years, cross-border transactions or substantial amounts are involved, prepare a correction schedule. Our accounting team can review the position alongside your bookkeeping.