diff --git a/mysql/tables/llx_bank_account.sql b/mysql/tables/llx_bank_account.sql
index 37d7daede51..5dca73fa633 100644
--- a/mysql/tables/llx_bank_account.sql
+++ b/mysql/tables/llx_bank_account.sql
@@ -37,7 +37,7 @@ create table llx_bank_account
   number         varchar(255),
   cle_rib        varchar(5),
   bic            varchar(11),
-  iban_prefix    varchar(50),                 -- Code IBAN
+  iban_prefix    varchar(34),                 -- 34 according to ISO 13616
   country_iban   varchar(2),
   cle_iban       varchar(2),
   domiciliation  varchar(255),
diff --git a/mysql/tables/llx_societe_rib.sql b/mysql/tables/llx_societe_rib.sql
index 6e5bb971530..c710d006428 100644
--- a/mysql/tables/llx_societe_rib.sql
+++ b/mysql/tables/llx_societe_rib.sql
@@ -32,7 +32,7 @@ create table llx_societe_rib
   number         varchar(255),
   cle_rib        varchar(5),
   bic            varchar(10),
-  iban_prefix    varchar(50),
+  iban_prefix    varchar(34),	-- 34 according to ISO 13616
   domiciliation  varchar(255),
   proprio        varchar(60),
   adresse_proprio varchar(255)