How to invoice international clients in Singapore (2026 guide)

Key Takeaways:

• When invoicing international clients, agree on the invoice currency upfront. This affects who pays conversion costs and who bears the risk if exchange rates change.

• Watch out for hidden FX costs. With bank transfers, the exchange rate can cost you more than the transfer fee. 

• Airwallex lets you invoice in 130+ currencies, save up to 80% on FX fees when converting currencies, and reduce manual work by automatically matching online invoice payments to their invoices.

How you invoice international clients from Singapore affects more than just how you get paid.

The currency you charge in, the payment method your client uses and what you do with the money afterwards can all affect how much you actually receive.

This guide covers how to choose an invoice currency, what to include on an international invoice, how to receive cross-border payments and how to manage foreign currency costs when doing business with clients overseas.

How to invoice international clients from Singapore

Follow these five steps for every overseas client, whatever the size of the invoice.

1. Agree the currency and payment terms in writing. Put the invoice currency, due date, and who pays bank charges in your contract or order form.

2. Issue the invoice with the right details. Include both legal entity names, a unique invoice number, the three-letter currency code, and your payment details.

3. Offer payment methods that suit your client. Common options are a local bank transfer, a Society for Worldwide Interbank Financial Telecommunication (SWIFT) transfer, or a payment link.

4. Receive the money in the invoice currency. This stops a bank converting it before you decide to.

5. Convert only what you need. Hold the rest and spend it in the same currency.

How to invoice international clients from Singapore

Follow these five steps to invoice overseas clients and manage the payment from start to finish:

1. Agree on the currency and payment terms upfront. Specify the invoice currency, payment deadline and who covers bank charges in your contract or order form.

2. Include the right details on your invoice. Add both parties’ legal names, a unique invoice number, the three-letter currency code and your payment instructions.

3. Choose a payment method that works for your client. Options include local bank transfers, SWIFT transfers and online payment links, depending on where your client is based and what your business supports.

4. Receive payment in the invoice currency. Where possible, use an account that can receive and hold that currency, rather than having the funds automatically converted on arrival.

5. Convert only what you need. Keep the remaining funds in the original currency and use them to pay expenses in that currency, where supported, to avoid unnecessary conversions.

The hidden costs of FX spreads and SWIFT fees

The transfer fee your bank quotes is rarely the full cost of receiving an international payment. A large part of the cost can be hidden in the exchange rate, with additional charges deducted along the way.

What a foreign exchange spread is

A foreign exchange (FX) spread, also called a markup, is the difference between the mid-market rate and the rate your provider offers. The mid-market rate is the midpoint between the buy and sell prices in the currency market.

Singapore banks generally don’t publish their FX markups, but a typical range is 1% to 3%. On a US$10,000 invoice, you could lose US$100 to US$300 when you’re converting the money.

In contrast, some fintech platforms publish their FX pricing upfront, making costs easier to compare.

For example, Airwallex charges 0.4% to 0.6% above the interbank rate, saving you up to 80% on FX fees as compared to traditional banks.

Other fees to watch out for

FX markups aren’t the only cost to watch. SWIFT payments may pass through intermediary banks, which can deduct their own fees before the money reaches you. Your bank may also charge an incoming transfer fee.

For example, DBS charges S$10 for an incoming telegraphic transfer. It also automatically converts incoming foreign currency to SGD unless you receive it into an eligible foreign-currency or multi-currency account.¹

Want to save on transfer fees? 94% of Airwallex Transfers go through local rails instead of SWIFT, with $0 transfer fees.

How to work out your own markup

To estimate the FX markup on your payment, compare the SGD amount your bank credited with the amount you would have received at the mid-market rate on the day of conversion.

Markup (%) = (SGD value at mid-market − SGD amount received) ÷ SGD value at mid-market × 100

For example, if US$10,000 was worth S$13,000 at the mid-market rate but your bank credited S$12,805, the difference is S$195, or 1.5%.

For a step-by-step guide, read our article on hidden bank fees in Singapore.

Which currency should you invoice in: SGD, USD, or your client’s currency?

The currency you invoice in affects who bears exchange rate risk, who pays to convert the money and how easy it is for your client to pay.

Each option has different trade-offs for you and your client:

Here are the three questions to help you decide which option to go with:

• What currency do you spend? If you pay for software, advertising, or other USD expenses, invoicing in USD lets you use that revenue for those expenses without converting it first, provided your account supports this.

• What does your client prefer? Invoicing in a currency your client already uses may make payment easier. If they have to convert funds just to pay you, they may factor that cost into their decision.

• Can you hold or spend the currency you receive? If your account automatically converts incoming payments to SGD, you may incur conversion costs even when you would rather keep the funds in their original currency.

Looking for an account that lets you hold and spend USD? With Airwallex, you can settle in 14 currencies including USD. This helps you avoid conversions and save on FX fees.

A note on GST

If you’re GST-registered and issue a tax invoice in a foreign currency, certain amounts may need to be shown in S$ using exchange rates accepted by IRAS.

Read our guide to GST invoice requirements in Singapore for more details.

Example: a Singapore agency invoices a US client in USD

Imagine your agency invoices a US client US$10,000 a month.

Out of that amount, US$3,000 goes towards software and advertising billed in USD, while the remaining US$7,000 covers expenses such as payroll and rent in SGD.

How you receive and hold the payment affects how much you'll pay in FX fees:

Note: This comparison covers FX fees only, not transfer fees. The bank route assumes your bank converts incoming USD to SGD.

On top of that, keep in mind that banks may not clearly disclose the markup built into their exchange rates, making it harder to see the full cost of converting money.

In contrast, some fintech providers publish their FX fees upfront, so you can compare the cost more easily. For example, Airwallex charges 0.4% to 0.6% above the interbank rate, saving you up to 80% on FX fees as compared to traditional banks.

Payment methods for overseas clients and what they cost you

Once you’ve decided how you want to receive and hold your client’s payment, consider how they’ll send it. Your options depend on the payment methods your provider supports, and each comes with different costs and levels of convenience.

A common way to receive international payments is through a SWIFT transfer.

However, intermediary banks may deduct fees along the way, making it difficult to know exactly how much you’ll receive. Your own bank may also charge an incoming transfer fee or apply an FX markup if it converts the payment into SGD.

If you prefer to receive payments by SWIFT, you can continue doing so through a traditional bank or a fintech provider that supports SWIFT transfers, such as Airwallex.

Alternatively, Airwallex offers other ways to collect payments, including local bank transfers, card payments and local payment methods. Here’s a quick overview:

Airwallex fees are based on its Singapore pricing as of 22 October 2026.

How to avoid delays on overseas invoices from Singapore

International payments can be delayed by bank processing times, intermediary fees or missing payment details. A few checks before you send an invoice can help your client pay on time and make it easier for you to track the payment when it arrives.

Why international payments get delayed

SWIFT transfers may pass through intermediary banks, which can deduct fees before the money reaches you. This can leave you receiving less than the invoiced amount.

Missing payment references or incorrect account details can also delay processing or make it harder to match a payment to the right invoice.

Transfer times vary by bank, currency and destination. For more details, see our guide to how long a bank transfer takes in Singapore.

What to include on your invoice

Before sending an invoice, make sure it includes:

• Payment terms and due date: State when payment is due and any agreed terms.

• Correct payment details: Provide account details that match the invoice currency and payment method.

• Payment reference: Ask your client to include the invoice number so you can identify the payment when it arrives.

• Bank charge arrangements: Specify who is responsible for transfer fees, including any intermediary bank charges.

• A convenient way to pay: Where available, offer local bank details in your client’s country to reduce reliance on intermediary banks.

How Chronos Agency reduced payment delays with Airwallex

Chronos Agency, a Singapore-based retention marketing agency, previously created invoices in Xero and sent payment instructions or links separately by email. It now embeds payment links directly in its Xero invoices, making it easier for clients to pay.

With this setup, client payments settle in three to four days, compared with more than a week previously.

GST and invoicing overseas clients: what to check with IRAS

Providing services to an overseas client doesn’t automatically mean you can charge 0% GST.

To zero-rate a service, it must meet the conditions under Section 21(3) of the GST Act. Depending on the type of service, the customer’s location and other circumstances may also affect whether zero-rating applies.

Check the IRAS guidance on providing international services to see whether your services qualify. For the required tax invoice details and formats, read our guide to GST invoice requirements in Singapore.

International invoice checklist

Before sending an invoice to an overseas client, check that it includes the details below. You can use this list to build a reusable invoice template, with optional fields added when relevant.

Invoice details

• Your legal business name and address, and your client’s name and address

• A unique invoice number

• The invoice date and payment due date

• A clear description of the goods or services provided

• The amount due and the three-letter currency code, such as USD or SGD

• A purchase order number or client tax ID, if required by your client

• The required tax details and wording, if GST applies and you need to issue a tax invoice

Payment details

• The account name and payment details for receiving the invoice currency, such as local account details or a SWIFT code, depending on the payment method

• Local bank details in your client’s country, if available and suitable for the payment

• A payment link, if you accept card payments or supported local payment methods

• The invoice number as the payment reference, with a request for your client to include it when paying

Terms to clarify upfront

• Payment terms, such as payment within 30 days (net 30)

• Who is responsible for bank and intermediary transfer charges

• The exchange rate source and date, or an agreed rate, if relevant to the transaction

• A contact for billing questions or payment issues

If you’re updating an existing invoice template, start with the currency code, payment reference and bank charge arrangements.

These details help both sides understand how much is due, how to pay and how to identify the payment when it arrives.

How Airwallex supports international invoicing

Airwallex helps you invoice overseas clients, collect payments and manage the money you receive across currencies. Here’s what you can do with Airwallex:

• Invoice in 130+ currencies using Airwallex Invoicing, and let clients pay through digital links supporting 160+ local payment methods.

• Receive and settle in the same currency across 14 supported settlement currencies, so your payments aren’t automatically converted to SGD.

• Receive payments using local bank details Cash Accounts, helping clients pay through local banking networks where supported.

• Save up to 80% on FX fees as compared to traditional banks, with competitive FX pricing of 0.4% to 0.6% above interbank.

• Reduce manual reconciliation by automatically matching online invoice payments to their invoices.

You can sign up for an Airwallex account fully online, with no setup fees, monthly fees or minimum balance requirements on the free Explore plan.

Frequently asked questions

How do I invoice international clients from Singapore?

Agree the currency and payment terms in writing, then issue an invoice with the right details. Offer payment methods your client can use easily, and receive the money in the invoice currency. Convert only the amount you need to SGD. The checklist above covers the fields to include.

What currency should I invoice foreign clients in?

Choose the currency that fits your costs and your client’s preference. An SGD invoice puts exchange rate risk on your client, while USD or your client’s currency makes payment easier for them but exposes you to rate moves. If you have USD costs, invoicing in USD lets you spend what you earn without converting it.

How do I avoid FX fees when invoicing overseas clients?

Receive payment in the invoice currency, and convert it only when you need to. Banks typically add a markup of 1% to 3% to the exchange rate, so converting twice means paying that cost twice. With an Airwallex Business Account, you can hold USD and spend it on USD costs, then convert the rest at competitive FX rates that save you up to 80% on FX fees as compared to traditional banks.

Who pays bank charges on an international invoice?

It depends on what you agree, so state it on the invoice. If your client sends the payment with shared charges, intermediary bank fees can reduce the amount you receive. Agree who covers these charges before the first payment, to avoid short payments and disputes.

Do I charge GST on invoices to overseas clients?

Not always. Only services that fall within Section 21(3) of the GST Act can be zero-rated, and IRAS says not all services to overseas customers qualify. Check the IRAS guidance, or ask a tax professional about your own situation.

How long does it take to receive an international payment in Singapore?

It depends on the route. SWIFT payments pass through intermediary banks, and cut-off times and public holidays can add delay. Payments through local bank rails in your client’s country involve fewer steps. If a payment hasn’t arrived, ask your client for a payment confirmation so you can trace it.

Sources:

1. https://www.dbs.com.sg/personal/support/bank-receive-funds-from-others.html