# BH-IBAN-01 — Invalid IBAN check digits

> https://billhorse.com/en/rules/bh-iban-01/

## What does this error mean?

The IBAN in the payment account (BT-84) fails the check-digit validation (ISO 13616, mod 97) — usually a typo or transposed digits.

## How to fix it

Compare the IBAN with the bank statement and correct it. Spaces are allowed and not an error.