Cal11 calculator
Search calculator...

Usa Iban Calculator

Reviewed by Calculator Editorial Team

An International Bank Account Number (IBAN) is a standardized way to identify bank accounts across different countries. For US bank accounts, the IBAN format follows specific rules that differ from traditional US routing and account numbers. This calculator helps you generate the correct IBAN format for US bank accounts.

What is an IBAN?

An IBAN (International Bank Account Number) is an internationally agreed system of identifying bank accounts across national borders. Each IBAN consists of up to 34 alphanumeric characters and includes a country code, check digits, and the domestic bank account number.

IBANs are used for international wire transfers to ensure accurate and efficient fund transfers between banks in different countries. The format and length of IBANs vary by country, with some countries not using IBANs at all.

Note: The United States does not officially use IBANs for domestic transactions, but the format is used for international transfers to US accounts.

USA IBAN Format

The IBAN for US bank accounts follows this format:

USkkbbbbbbbbbbbbbbbbbbbbbbbb

  • US - Country code for the United States
  • kk - Two check digits calculated using the IBAN checksum algorithm
  • bbbbbbbbbbbbbbbbbbbbbbbb - The domestic bank account number (BBAN) with leading zeros if necessary to make it 23 characters long

The BBAN for US accounts typically consists of:

  • Routing number (9 digits)
  • Account number (12 digits)
  • Check digit (1 digit)

When creating the IBAN, the BBAN is padded with leading zeros to make it exactly 23 characters long.

How to Calculate USA IBAN

To calculate the IBAN for a US bank account, follow these steps:

  1. Get the 9-digit routing number and 12-digit account number from your bank
  2. Calculate the check digit for the account number using the US check digit algorithm
  3. Combine the routing number, account number, and check digit to form the 23-digit BBAN
  4. Add the country code "US" and two check digits to the beginning of the BBAN
  5. Calculate the two check digits using the IBAN checksum algorithm
  6. Combine all parts to form the complete 34-character IBAN

IBAN Checksum Algorithm

The check digits are calculated using the following steps:

  1. Move the four initial characters to the end of the string
  2. Replace each letter in the string with two digits, thereby expanding the string, where A = 10, B = 11, ..., Z = 35
  3. Convert the string to an integer
  4. Calculate 98 minus the modulo 97 of the integer
  5. If the result is a single digit number, prefix it with a 0 to make it two digits

Examples

Here are two examples of how to calculate the IBAN for US bank accounts:

Example 1

Routing number: 123456789

Account number: 123456789012

Check digit: 3 (calculated using US check digit algorithm)

BBAN: 1234567891234567890123

IBAN: US331234567891234567890123

Example 2

Routing number: 987654321

Account number: 987654321098

Check digit: 7 (calculated using US check digit algorithm)

BBAN: 9876543219876543210987

IBAN: US879876543219876543210987

FAQ

Do US banks use IBANs?

The United States does not officially use IBANs for domestic transactions, but the IBAN format is used for international transfers to US accounts.

How long is a US IBAN?

A US IBAN is 34 characters long, consisting of the country code (US), two check digits, and a 23-character BBAN.

Can I use the IBAN calculator for any US bank?

Yes, this calculator can generate IBANs for any US bank account as long as you have the routing number and account number.

Is the IBAN the same as the account number?

No, the IBAN is a standardized international format that includes the country code, check digits, and the domestic bank account number.