Which currency, and which exchange rate, a Swedish invoice has to use.

The provision

Sweden answers the currency question on the invoice itself.

Whatever currency an invoice uses, the VAT amount must also be stated in Swedish kronor if the tax is to be paid to the state; a business that keeps its accounts in euro states it in euro instead. Because the rule is conditioned on the tax being payable, a reverse-charge invoice to a platform, which carries no Swedish tax, carries no kronor figure either.

«Oavsett i vilken valuta beloppen i en faktura anges ska mervärdesskattebeloppet även anges i svenska kronor om mervärdesskatten ska betalas till staten.»

Whatever currency the amounts on an invoice are given in, the VAT amount must also be given in Swedish kronor if the VAT is to be paid to the state.

17 kap. 29 §, mervärdesskattelagen (2023:200)

When it reaches you

If you sell through the stores, this bites in one case.

Article 230 constrains the amount of VAT payable or to be adjusted. An app developer's ordinary invoice to a store or an ad network carries no VAT amount at all: it is a reverse-charge supply to another member state, or a supply outside the scope entirely. Where there is no tax line, there is nothing for the currency rule to bind. The rule reaches you on a supply that actually charges Sweden VAT.

What Ureta does about it

The rate is pinned when the month is, and it is kept with the document.

• The ECB reference rate, for every EU tenant. It is the rate article 91(2) obliges every member state to accept. A currency other than the euro is converted through the euro, as the same article says.
• The rate is pinned per month and stored, so a document issued last March still reports the rate it carried in March rather than a number recomputed today.
• Nothing is guessed. Where no rate from a defensible authority is available for a currency, the engine refuses to issue rather than putting a plausible wrong number on a legal document.