Invoicing international clients: currency, rates and getting paid

Which currency should you bill in?

There are three sensible answers, and the right one depends on who is absorbing the risk.

**Your own currency** is simplest. Your books balance, there is nothing to convert, and the exchange risk sits with the client. This is the default for most small suppliers and is entirely normal — plenty of clients pay foreign-currency invoices without blinking.

**The client's currency** makes you easier to buy from. Procurement teams and finance departments at larger companies often prefer or require it, and quoting in the buyer's currency removes a small barrier at the point of sale. The cost is that you now carry the FX risk between quote and payment.

**A neutral third currency** — usually USD or EUR — is common in agencies, shipping and anything traded internationally, and works well when neither side's currency is widely held.

Whichever you choose, think about the time horizon. On a two-week job, rate movement is noise. On a six-month fixed-price project or a multi-year retainer, a 5–10% swing is entirely ordinary, and that comes straight out of your margin. For long engagements, either bill in your own currency, re-price annually, or agree a clause that revisits the rate if it moves beyond a stated band.

State the currency so it cannot be misread

Use ISO 4217 three-letter codes. The dollar sign is shared by USD, AUD, CAD, NZD, SGD, HKD and several others; "$1,200.00" on an invoice from an Australian supplier to an American client is a genuine ambiguity worth roughly 35% of the invoice value. Write **EUR 1,200.00** or **1,200.00 AUD** and use the same placement throughout the document — line items, subtotal, tax, total.

Two more details that cause avoidable confusion:

- **Decimal separators.** Germany, France, Spain and much of Europe write 1.200,00 where the UK, US and Australia write 1,200.00. The ISO code plus consistent formatting resolves it; do not mix conventions in one document. - **Minor units.** Most currencies have two decimal places, but JPY is conventionally written without them (JPY 150,000, not JPY 150,000.00). A handful of others use three. If your invoice tool forces two decimals on JPY, it looks amateurish to a Japanese client.

Crossbill supports 25+ currencies and prints the ISO code alongside every amount by default, so the ambiguity does not arise.

Exchange-rate notes and your accounting currency

If you invoice in a currency other than the one you keep your books in, add an exchange-rate note. It costs one line and saves arguments later:

> Converted at EUR 1 = AUD 1.6420 (ECB reference rate, 30 June 2026).

Three elements matter: the rate, the source, and the date. "At today's rate" is not a rate. The European Central Bank publishes daily euro reference rates; most central banks publish equivalents, and tax authorities frequently publish their own official rates — HMRC, for instance, publishes monthly rates for VAT and customs purposes.

This is not merely tidiness. Where VAT is due on a foreign-currency invoice, the VAT amount usually has to be expressed in the local currency: EU rules (Article 230 of the VAT Directive) require the VAT payable to be shown in the national currency of the member state where the supply takes place, and UK guidance similarly requires the sterling equivalent of the VAT on the invoice. The rate you may use for that conversion is often prescribed. If your invoice carries VAT or GST, check the rule for that jurisdiction rather than assuming your own applies.

Round once, at the end

Rounding errors on international invoices are almost always self-inflicted. The pattern is: convert each line to the target currency, round each converted line to two decimals, then add them up — and the total is a few cents adrift from the same calculation done the other way round. Your client's accounts payable system then flags a mismatch and someone emails you about eleven cents.

The fix is to do it in one direction and round once. Calculate line amounts at full precision, sum them, apply any tax at full precision, and round the final figures to the currency's minor unit at the last step. If you are converting, apply the conversion to the total rather than line by line, and keep the rate itself at four to six decimal places — a rate rounded to two decimals introduces error of its own.

Some tax authorities specify their own rounding rules for VAT amounts (including, in places, rounding conventions that differ from ordinary half-up rounding), so if a VAT figure is involved, check the local guidance. Crossbill calculates at full precision and rounds once at the total, which is the behaviour you want by default.

Getting paid across borders

Give the client whatever local payment rail exists in their country and you will be paid faster and more cheaply than via a SWIFT wire. That means IBAN and BIC for EUR (SEPA), sort code and account number for GBP, BSB and account number for AUD, and routing number plus account number for USD ACH. Multi-currency accounts from providers such as Wise, Revolut Business or Payoneer give you local details in several currencies without opening foreign bank accounts.

Where a genuine international wire is unavoidable, agree who pays the charges. SWIFT payments carry a charge instruction — OUR (sender pays all), SHA (shared, the default) or BEN (beneficiary pays) — and intermediary correspondent banks can deduct fees en route, which is why an invoice for USD 2,000 sometimes lands as USD 1,978. Say on the invoice which party bears bank charges so the shortfall is not a surprise on either side.

Payment links via Stripe, PayPal or similar are convenient and often worth it for smaller invoices, but card and wallet conversion typically carries a spread of a few percent over the mid-market rate on top of the processing fee. Check the current schedule and decide whether you absorb it or price it in. Finally: state your payment terms, a reference the client can quote, and — if you supply certain countries — be aware that withholding tax may be deducted at source. Ask the client early rather than discovering it on the remittance advice.

This page is practical guidance, not tax or legal advice. VAT, GST and withholding treatment of cross-border supplies varies by country and by what you sell; check your position with an accountant.