Booking foreign currencies: how to apply FTA and FOCBS exchange rates

Many Swiss SMEs buy software in dollars, source goods from the eurozone or invoice customers in Germany in euros. For bookkeeping and VAT, these amounts have to be converted into Swiss francs. The rules on which rate to use are clear, but they are often applied incorrectly.

Two levels: bookkeeping and VAT

The Swiss Code of Obligations (CO/OR) requires accounts to be kept in the national currency or in the currency that is essential to the business. If the annual accounts are not prepared in Swiss francs, the figures must also be stated in francs and the exchange rates used must be disclosed in the notes (Arts 957a and 958d CO). For most SMEs, the Swiss franc is the accounting currency and foreign currency transactions are converted.

VAT is always accounted for in Swiss francs. Here, Art. 45 of the VAT Ordinance sets out precisely which rate to use.

The VAT rule: monthly average or daily rate

To convert consideration in a foreign currency, you can choose between:

• the monthly average rate published by the Swiss Federal Tax Administration (FTA/ESTV), or
• the daily selling rate for foreign exchange (Devisen Verkauf).

Companies that belong to a group can use their group conversion rate instead. Whichever approach you choose must be kept for at least one tax period. For currencies for which the FTA does not publish a rate, the published daily selling rate of a Swiss bank applies.

What counts is the point at which the tax claim arises. If you account on the basis of agreed consideration, which is the norm, you use the invoice date for your outgoing invoices. For input tax, what counts is the point at which the right to deduct input tax arises, which under agreed consideration is when you receive the invoice.

Whether a supply is invoiced in a foreign currency depends on the invoice, not on the payment. An invoice in euros remains consideration in a foreign currency, even if the customer pays in francs.

Where to find the rates

The daily rates are supplied by the Federal Office for Customs and Border Security (FOCBS/BAZG) and are available on the FOCBS exchange rate page. They are available Monday to Friday, except on public holidays, from 1 pm at the latest. If the day's rate has not yet been published, you may use the most recent daily rate.

The monthly average rate is the average of the daily rates from the 25th of one month to the 24th of the following month. It is published on the 25th and applies for the following calendar month. For October 2026, for example, the monthly average VAT rate is 0.9507 francs per euro and 0.8218 francs per US dollar.

For direct taxes, the FTA publishes its own rate lists, including annual average rates and rates as at 31 December. These are used, among other things, to convert income and assets into francs.

Example: a euro invoice to a Swiss customer

An engineering firm in Zurich uses the effective method and monthly average rates. On 15 October 2026, it invoices a Swiss customer EUR 5,000 plus 8.1% VAT, a total of EUR 5,405.

Conversion at the October monthly average rate (0.9507):

The receivable is booked at CHF 5,138.53, of which CHF 385.03 is VAT owed.

The customer pays on 14 November. The bank credits the euro amount at its own rate, assumed here to be 0.9450, which gives CHF 5,107.72. The difference of CHF 30.81 is an exchange loss and is booked as a financial expense. The VAT stays at CHF 385.03, because it is based on the rate at the time the tax claim arose, not on the later payment.

Example: input tax on a euro invoice

Incoming invoices in a foreign currency must also be converted for input tax purposes. Art. 58 of the VAT Ordinance refers to the same rules as for turnover.

On 20 October 2026, a Swiss supplier invoices the engineering firm EUR 2,000 plus 8.1% VAT, making EUR 2,162. At the October monthly average rate of 0.9507, this gives:

The input tax of CHF 154.01 is claimed in the VAT return for the fourth quarter. If the firm pays the invoice later at a different rate, this again creates an exchange difference, booked as financial income or financial expense. The input tax stays the same.

Booking exchange differences correctly

• Realised exchange differences arise when a payment is received or a supplier invoice is paid. They belong in financial income or financial expense.
• Foreign currency accounts (such as a EUR bank account) are kept at the rate of each individual entry. At month-end or year-end, you adjust the franc value.
• No VAT on exchange differences: they do not change the consideration that counts for VAT.

Valuation at the balance sheet date

At year-end, the balance sheet often still contains open receivables, payables or bank balances in foreign currencies. In practice, these are valued at the rate on the balance sheet date. The principle of prudent valuation applies (Art. 960 CO): if there are specific indications that assets are overvalued, the values must be reviewed and adjusted. Agree with your accountant how to handle unrealised exchange gains, and then treat them the same way every year, because the law requires consistent standards of presentation and valuation.

Common mistakes

1. Bank rate instead of FTA rate for VAT: for VAT, the FTA rates or the daily selling rate for foreign exchange apply. Your bank's rate is only permitted if the FTA does not publish a rate for that currency.
2. Switching method mid-year: the monthly average or daily rate must be kept for at least one tax period.
3. Exchange differences treated as turnover: exchange gains are not turnover and not a supply subject to VAT.
4. Payment date instead of invoice date: if you account on the basis of agreed consideration, the invoice date is what counts.
5. Input tax in foreign currency converted incorrectly: Art. 45 of the VAT Ordinance applies to input tax by analogy too (Art. 58 VAT Ordinance).

Practical checklist

1. Decide on your method, monthly average or daily rate, and document it.
2. Take rates from the official source, not from any random website.
3. Record foreign currency invoices with the original amount, the rate and the franc amount.
4. Book exchange differences separately when payments come in.
5. Revalue foreign currency accounts at least at year-end.
6. For group companies: apply the group rate consistently to all supplies.

Accounting software can take care of much of this. In Buchsnap, receipts in foreign currencies are converted at your chosen rate, the original amount stays visible, and exchange differences on incoming payments are suggested as a separate entry.

Last updated: October 2026. This article does not replace individual advice.