At Azimo, we’re constantly looking for ways to make the world of money transfer simpler for our customers. That’s why we’ve created our Ask Azimo series: to show you how sending money works and answer some of your most frequently asked questions about international transfers. This week: IBAN numbers.

What is an IBAN number?

The name stands for International Bank Account Number (IBAN) – so, basically it’s a bank account number. It’s the internationally agreed standard for numbering bank accounts across many countries – 69 at the time of writing.

Who came up with them?

We have the Europeans to thank for this one: IBANs were first dreamt up in 1997 by the European Committee for Banking Standards as a way of simplifying cross-border payments within the EU. Since then lots of other countries have adopted the idea. It might sound boring but this intelligent numbering system has slashed international payment errors over the years.

Why do we need IBANs?

Back in the bad old pre-IBAN days, account number formats varied wildly both from bank to bank and from country to country. Obviously this caused problems. Also it wasn’t possible for banks or money transfer companies to check whether an account number was in the right format before sending money. As a result, there were delays, unnecessary extra costs, and payments that sometimes went missing.

Does an IBAN replace my account number and sort code?

An IBAN number should be all the information that you need, in fact, in many countries in Europe (e.g. Germany & Spain) an IBAN number is the standard way of communicating bank account details.
In other countries (e.g. the UK ) an IBAN doesn’t replace your sort code and bank account number. Here an IBAN is used as an additional number with extra information and checking procedures built-in to help overseas banks identify an account when handling international payments.

When making an international payment to an IBAN-compliant country using Azimo, you’ll normally not need to provide BIC (Bank Identifier Code) of the beneficiary (for BIC codes explained, click here) as we use some very clever tech that works these details out from the IBAN.

But when receiving a payment, you’ll normally need to provide the payer with your IBAN and BIC (well, not everyone’s got the tech we have).

What do all the letters and numbers mean?

This is when things get a bit detailed, but if you are interested the structure of an IBAN is set but the length (up to 34 characters) depends on the country in which it’s issued.

All IBANs are made up of:

  • country code – two letters
  • check digits – two numbers
  • basic bank account number (BBAN) – up to 30 characters showing specific bank and account details

IBANs don’t contain spaces, however when printed they are sometimes shown in groups of four characters separated by a single space. The last group being of variable length.

In Poland, for instance, the IBAN is composed of 28 characters (both letters and numbers) and is constructed by inserting the country code PL before the NRB number (Polish bank account number), which creates the following format:

PLkk bbbs ssss cccc cccc cccc cccc

First two characters: the country code (PL for Poland).

Next two characters: the check digits (kk).

Next three characters: the national bank code (bbb).

Next five characters: the branch code (sssss).

Next 16 characters: the account number (cccccccccccccccc).

What are the check digits in an IBAN?

These two digits are designed to allow sending customers, banks and money transfer companies to validate the account number provided and make sure that the IBAN is correct. This hugely reduces errors.

Which countries are IBAN-compliant?

Well, the number’s is growing every year. Today IBANs are used by all EU countries, EEA (European Economic Area) members, Switzerland and several countries across the Middle East, Central America and Caribbean. For a full list of IBAN-compliant countries, click here.

Hope you found this useful and interesting. And if you’ve a suggestion for an Ask Azimo topic, please email:

Azimo is the better way to transfer money around the world, touching millions of people’s lives. Fast, simple and safe, Azimo has the largest digital network in the world, enabling customers to send money to more than 190 countries from any internet-connected device.