Currency Exchange Tips for International Invoicing

Currency exchange on an invoice comes down to four decisions: which rate, which date, what to print, and what to do when the money lands short or long. This article covers those mechanics for one invoice at a time. Deciding which currency to quote in belongs to multi-currency pricing strategy, and protecting a long contract against currency moves belongs to hedging currency risk.

Last reviewed: 27 October 2026. This is general information, not tax or accounting advice. VAT and currency rules differ by country, so check with your tax authority or an adviser before you rely on a method.

Which exchange rate should you use on an invoice?

Use a rate that is published, dated and checkable by someone else, and use the same source every time. Tax authorities care less about which reputable source you pick than about whether you apply it consistently.

Two practical notes on the sources themselves:

• ECB euro reference rates are usually updated around 16:00 CET on every working day, and the ECB says they are "published for information purposes only" (ECB, accessed 27 October 2026). They are a reference, not the rate your bank will give you. For a pair that does not involve the euro, Article 91 says to convert through each currency's euro rate.
• HMRC monthly exchange rates are published on the penultimate Thursday of each month and apply to the following calendar month. They are quoted as currency units per £1 (UK Trade Tariff: monthly exchange rates). For October 2026 the US dollar rate is 1.3456 per £1.

If you only need a quick reference figure, the invoice currency converter uses a dated ECB snapshot (27 October 2026) and lets you type your own rate instead. It is not a live feed.

Which date should the rate come from?

The rate belongs to the date the tax rules or your contract point to. Mixing dates is where most mismatches start.

1. Tax point or invoice date for any figure that feeds a VAT return. HMRC says the rate to use is the one "current at the time of the supply", whatever method you adopt. Under Article 91, the EU rate is the one recorded when VAT becomes chargeable.
2. Payment date for what you actually received. The IRS points to the rate when you receive, pay or accrue the item, so your bookkeeping will usually record the invoice at one rate and the receipt at another.
3. Contract lock date only if the contract fixes a rate. If you promised "USD 4,000 at 1.10 EUR/USD", that agreement governs what the client owes, but it does not replace the tax-authority rule for the VAT figure.

Write the rule into your terms once, then repeat it on every invoice: "Converted amounts use the ECB euro reference rate published on the invoice date." Your client's accounts payable team can then reproduce your number in a minute instead of emailing you.

What to print when an invoice involves two currencies

An invoice that converts anything should let a reader rebuild the calculation without asking you. Print these items:

• The invoice currency as an ISO code (USD, EUR, GBP) next to the totals. Symbols are ambiguous: "$" is used by several currencies.
• The rate, written in one direction, with its source and date: "USD 1.3456 = GBP 1 (HMRC period rate, October 2026)".
• The converted figure the law requires, not every converted figure. A UK VAT invoice in dollars must show the VAT total in sterling. The net total "can be expressed in any currency" (VAT Notice 700, section 16.3.1).
• Who bears bank and conversion charges, for example "All bank charges on the payer's side are for the payer's account. Please send the full invoice amount."
• The payment currency if it differs from the invoice currency, and the account details for that currency.

For the full list of fields every invoice needs, see what to include on an invoice. For VAT-specific fields such as the VAT number, see the VAT invoicing guide.

Worked example 1: a UK VAT invoice issued in US dollars

Inputs. A UK VAT-registered design studio invoices a UK company (the UK subsidiary of a US group that budgets in dollars) for a standard-rated service. Tax point: Tuesday 20 October 2026. Net fee USD 4,000. UK standard VAT rate 20% (GOV.UK VAT rates). The studio uses HMRC's period rate, which for October 2026 is USD 1.3456 per £1.

Method. VAT = 4,000 × 20% = USD 800.00. Sterling VAT = 800 ÷ 1.3456 = £594.53. Only the bold figure has to be in sterling on the invoice. The other sterling figures are optional, but showing them makes the client's VAT reclaim easier to check.

Printed note: "VAT total in sterling: GBP 594.53, converted at HMRC's period rate for October 2026 (USD 1.3456 = GBP 1). VAT reg. no. GB 123 4567 89." (The VAT number here is a placeholder.)

Once the studio uses the period rate, HMRC says it cannot switch to another method without written agreement from HMRC's VAT Written Enquiries Team. So the choice is a policy decision, not a per-invoice one.

Worked example 2: a short payment after the rate moved

Inputs. A US freelancer invoices a German client EUR 3,000 on Tuesday 27 October 2026, net 30. The ECB reference rate that day is USD 1.1150 per EUR, so the freelancer records USD 3,345.00 of income. The numbers below are illustrative: suppose the euro weakens to 1.1050 by the payment date, and an intermediary bank deducts EUR 20.

What to do with each line:

• The USD 30.00 exchange loss is a realized currency difference. Record it in its own account (often called "realized FX gain/loss"), not as a reduction of sales. The invoice is still paid in full in euro terms.
• The EUR 20 bank fee is a short payment. If your terms said the payer covers its own bank's charges, ask for the EUR 20, or decide it is not worth chasing and record it as a bank charge. Either way, clear the invoice with a separate fee entry rather than editing the invoice amount, so your bank reconciliation still matches.

Exchange differences only arise when you invoice in a currency other than the one you keep your books in. That is the trade-off of invoicing in your client's currency, covered in invoicing in a foreign currency.

Who pays the conversion and transfer costs?

Say it in the contract and on the invoice, because otherwise each bank in the chain may take its cut from your amount.

• Invoice in your currency, client converts. The client sees the conversion cost on their side. You receive the full amount unless an intermediary deducts a fee.
• Invoice in the client's currency, you convert. You carry the exchange rate and any conversion fee. Payment providers often price conversion separately. For example, Stripe's US pricing page lists "+ 1%" "if currency conversion is required" and "+ 1.5%" for international cards (Stripe pricing, accessed 27 October 2026). Check your own provider's current pricing for your country.
• Hold the currency. If you have an account that holds the client's currency, you can delay conversion. You still record the income at the rate your tax rules require, and any later difference is an exchange gain or loss.

Tips that prevent the usual currency disputes

1. Quote and invoice in the same currency. Converting a quote into a different invoice currency invites "that is not what we agreed".
2. Match the purchase order. Many accounts payable teams cannot approve an invoice whose currency differs from the PO. Ask before you send the first invoice.
3. Round once, at the end. Convert totals, not each line, unless the law requires line-level figures. Round to the currency's minor unit (two decimals for USD, EUR and GBP; none for JPY).
4. Keep the rate evidence. Save the published rate for the date you used (a PDF or CSV of the ECB or HMRC table). If a tax inspector or client asks, you can show it.
5. Do not edit a sent invoice to absorb a rate change. Issue a credit note or record the difference in your books instead. See how to handle unpaid invoices if the client refuses the balance.
6. Use payment terms that keep the gap short. The longer the term, the further the rate can move between invoice and payment. Net 30 and its alternatives explains the trade-offs.

When this approach is not enough

• Long contracts with large foreign-currency receivables. A rate rule on the invoice records the conversion; it does not protect you from the rate moving over the months before payment. That needs pricing clauses or hedging; start with hedging currency risk.
• Countries with e-invoicing or clearance systems. Where invoices must be submitted in a structured format, currency fields and conversion rules are set by that system. A PDF with a note will not satisfy it. See how to invoice international clients.
• Bookkeeping in more than one functional currency. Groups with entities in several countries need accounting software that revalues open balances. A one-line invoice note is not a substitute.

How InvoiceQuickly handles currency today

Available now:

• Each invoice has one currency, chosen from USD, EUR, GBP, CAD, AUD, INR or PKR. Line items, tax and the total are all calculated and printed in that currency.
• The tax line is labelled "Tax (x%)" and calculated in the invoice currency only.
• The Notes and Terms fields (up to 5,000 characters each) print on the PDF. Use them for the rate note, the sterling or euro VAT figure, your fee policy and your VAT number. Business tax IDs are copied from settings to new invoice PDFs.
• On Pro, a Stripe or PayPal payment link charges the invoice's remaining balance in the invoice's currency.
• Dashboard totals are kept separate per currency rather than converted.

Not available today: exchange-rate lookup, automatic conversion, a second-currency column, or tax totals in a second currency. Work out the converted figure with an official table (or the currency converter) and type it into Notes. The Free plan covers 5 invoices; Pro is $9/month. See pricing.

For layouts to adapt, see the UK invoice template and the EU invoice template. They are reference layouts, so add any legally required details yourself.

Frequently asked questions

Do I have to use the central bank rate on an invoice?

Not always. In the UK you can use the UK market selling rate at the time of supply or HMRC's period rate without asking, and any other rate needs HMRC's written agreement. EU member states must accept the latest ECB rate but may also allow a market rate. For figures that do not feed a tax return, any named, dated rate agreed with your client works.

Can I issue an invoice in a foreign currency?

Yes, in the UK and EU. EU law says invoice amounts "may be expressed in any currency" as long as the VAT payable is stated in the national currency. HMRC requires only the VAT total to be in sterling on a UK VAT invoice; the net total can be in any currency.

Which date's exchange rate applies to an invoice?

For VAT, the rate current at the time of supply (the tax point) in the UK, and the rate when VAT becomes chargeable in the EU. For recording the receipt, the rate on the day you are paid. Write the rate date on the invoice so the client knows which one you used.

How do I calculate an exchange rate for an invoice amount?

Multiply or divide by the published rate, depending on its direction. HMRC quotes currency units per £1, so USD 800 ÷ 1.3456 = £594.53. The ECB quotes units per euro, so EUR 3,000 × 1.1150 = USD 3,345.00. For two non-euro currencies, convert through the euro.

What if the client pays less because of bank charges?

Record the shortfall as a bank charge or short payment, separate from any exchange difference, and decide whether to chase it. Avoid it next time with a line such as "Please send the full invoice amount; charges on the payer's side are for the payer's account."

Is an exchange rate difference a discount?

No. If the client paid the full amount in the invoice currency, the invoice is paid in full. A change in what that amount is worth in your home currency is an exchange gain or loss, recorded separately from sales.

Does InvoiceQuickly convert currencies automatically?

No. You choose one of seven currencies per invoice, and amounts are calculated in that currency. Add any converted VAT figure and its rate in the Notes field.

Invoice in your client's currency and keep the rate note on every PDF. Start free.