How to build an IBAN check into your payment process: done in two minutes

An IBAN check isn't an IT project — it's a habit that takes a few seconds. Here's how to work it into the moments that matter, without heavy procedures.

A new supplier, a one-off payment to a freelancer, or a refund to a customer. Before you transfer the money, you type over the IBAN from an email or PDF. Then what? Most accounting packages check whether the IBAN is technically valid — but not whether it actually belongs to the right party. In this post we show you how to build an IBAN check into your payment process in two minutes, without extra software and without burdening your colleagues with heavy procedures.

Why an IBAN check is more than just ticking a box

An IBAN consists of a country code, check digits, a bank code, and an account number. The check digits let any calculator verify that the structure is correct. But that tells you nothing about:

• Whether the IBAN is active at a Dutch bank.
• Which bank it belongs to (useful to compare with what the supplier tells you).
• Whether the IBAN matches the account holder name on the invoice.

That last point is exactly what invoice fraud exploits. Someone sends an email saying "we have a new account number," and if nobody looks beyond the structure, the money ends up in the wrong account.

The three moments where an IBAN check adds real value

1. When creating a new contact

Adding a new supplier or customer to your accounts? Paste the IBAN into a verification tool before you save it. A typo — say, a 0 instead of an O, or a transposed digit — will jump out straight away. That saves you a failed payment and an awkward phone call later.

2. Every time an existing IBAN changes

This is the moment fraudsters strike. "Our bank details have changed — please use this new IBAN going forward." Ground rule: never accept an IBAN change based solely on an email. Call the supplier on a number you already know (not the number in the email), and check whether the new IBAN is with the same bank you're used to. If a well-established company suddenly switches from a Dutch bank to a foreign account: stay extra alert.

3. For one-off payments to unfamiliar parties

Think refunds, deposits, or a quick purchase from a supplier you've never dealt with before. This is exactly where a typo or wrong IBAN can slip through. A 10-second check prevents the money going to a complete stranger.

How to set this up in practice (no policy document required)

You don't need a formal process for this. Three simple agreements are enough:

1. New IBAN = always check. Whoever creates a creditor or contact runs the IBAN through a verification tool. A screenshot or a quick note in the file: done.
2. Change = four-eyes principle. One person receives the request; a second person calls to verify and confirms in writing (internally) that the change has been made.
3. Above a threshold amount = extra check. Agree, for example: payments above €2,500 to a new party always require sign-off from two people.

These agreements fit on a single page and can be run through with your bookkeeper or office manager in five minutes.

What a good check tells you

A solid IBAN check answers the following:

• Is the structure valid (do the check digits add up)?
• Which bank does this IBAN belong to (ABN, ING, Rabobank, Bunq, etc.)?
• Which country is it from, and does that match what you'd expect?

What a free online check does not give you is the account holder name. For that you need to go to the bank itself (some banks offer a name-number check when making a transfer) or use a paid service. For SMBs, the combination of "quick IBAN check + a phone call when in doubt" is more than sufficient in most cases.

A quick bonus: check the VAT number too

With new suppliers it's worth checking the VAT number alongside the IBAN. Not because you distrust them, but because an incorrect or inactive VAT number can cause problems with the tax authorities later on — especially for intra-community invoices. Two tabs open, three minutes of work, done.

Common mistakes in SMBs

• Manually retyping an IBAN from a PDF without a double-check. One wrong digit and the money goes to someone else — and doesn't always come back.
• Relying on the "automatic recognition" of your accounting package. It checks structure, not context.
• Accepting changes via the same email thread as the invoice. If your supplier's inbox has been hacked, you're caught in the same thread.
• Keeping no log of who processed an IBAN change. If questions arise later, you'll have a hard time finding out.

In closing

An IBAN check is not an IT project. It's a habit that takes a few seconds and can save you a lot of money and embarrassment. Build it into the moments that matter — new contacts, changes, one-off payments — and you've covered 90% of the risks without anyone even noticing.

Want to try it right now? Use our free IBAN check to verify an account number, or the VAT check for new suppliers. Both run in your browser, no account needed.