Frequently asked questions

Who should be interested in ISO 20022?

Mostly financial institutions that want to streamline their communication infrastructure and associated costs by opting for a single, common "language" for all financial communications, whatever the business domain, the communication network and the counterparty (other financial institutions, clients, suppliers and market infrastructures). ISO 20022 is targeted at these standards initiatives that are generally driven by communities of users looking for more cost-effective communications to support specific financial business processes with a particular view of facilitating interoperability with other existing protocols.


What is ISO 20022?

ISO 20022 - Universal financial industry message scheme (which used to be also called "UNIFI") is the international standard that defines the ISO platform for the development of financial message standards. Its business modelling approach allows users and developers to represent financial business processes and underlying transactions in a formal but syntax-independent notation. These business transaction models are the "real" business standards. They can be converted into physical messages in the desired syntax. At the time ISO 20022 was developed, XML (eXtensible Mark-up Language) was the preferred syntax for e-communication. Therefore, the first edition of ISO 20022, published in December 2004, proposed a standardized XML-based syntax for messages. The second edition of the standard, published in May 2013, included the possibility to use ASN.1 as well. The standard was developed within the Technical Committee TC68 - Financial Services of ISO - the International Organization for Standardization.


What is the scope of ISO 20022?

The first focus of ISO 20022 is on international (cross-border) financial communication between financial institutions, their clients and the domestic or international 'market infrastructures' involved in the processing of financial transactions. There is, however, a strong opportunity to use ISO 20022 for the development of new domestic financial messages as well, thereby streamlining all communications for financial institutions.


Why was ISO 20022 developed?

The need for a ISO 20022 standard arose in the early 2000’s with the widespread growth of Internet Protocol (IP) networking, the emergence of XML as the 'de facto' open technical standard for electronic communications and the appearance of a multitude of uncoordinated XML-based standardization initiatives, each having used their own "XML dialect". The ISO 20022 standard offered a common way of using XML and a way to shield investments from future syntax changes by proposing a common business modelling methodology to capture, analyze and syntax-independently describe the business processes of potential users and their information needs. The 2013 edition of the ISO 20022 standard included the possibility to use ASN.1 in addition to the XML syntax.   


What is included in the ISO 20022 standard?

The standard itself describes the development methodology, the registration process and the organization of the central financial repository that contains the ISO 20022 messages and their components. The ISO 20022 standard consists of eight parts:

  • Part 1: Metamodel
  • Part 2: UML profile
  • Part 3: Modelling
  • Part 4: XML schema generation
  • Part 5: Reverse engineering
  • Part 6: Message transport characteristics
  • Part 7: Registration
  • Part 8: ASN.1 generation

Copies of the standard can be purchased from ISO at:

Note that, although they are often referred to as ISO standards, the ISO 20022 messages are not ISO standards. The ISO standard is the development methodology described in the eight parts described above. The messages are defined using this ISO 20022 development methodology: strictly speaking, they are ISO 20022 "compliant" messages, but we called them ISO 20022 messages. 


What will ISO 20022 accomplish?

The ISO 20022 flexible framework will encourage users to build business transactions and message models under an internationally agreed upon approach, and to migrate to the use of a common vocabulary and a common set of syntaxes. In ISO 20022, the models and the derived XML or ASN.1 outputs are stored in a central financial repository serviced by a Registration Authority. The ISO 20022 repository offers industry users and developers free access to a Data Dictionary of business and message components and a Business Process Catalogue containing message models and corresponding XML and/or ASN.1 schemas.

If there are no ISO 20022 messages to cover a specific transaction, standards initiatives can be launched to define new models and messages and submit the new solution for approval by the ISO 20022 registration bodies. If the messages exist in the ISO 20022 repository, but do not address all requirements of a new community, it can be agreed upon to update the existing models and messages and create a new version that will accommodate the needs of all.


Who handles the ISO 20022 registration process?

The ISO 20022 approval and registration process involves three kinds of registration bodies: the Registration Management Group (RMG), the Registration Authority (RA) and the Standards Evaluation Groups (SEGs), which work together to validate and process the registration requests from users, according to the ISO 20022 Registration Procedures


What is the role of the ISO 20022 Registration Management Group (RMG)?

Composed of senior industry experts nominated by ISO 20022 Member Entities, the RMG is the highest registration body. Its role is to promote and support the involvement of financial service actors to facilitate the registration and maintenance of high quality globally relevant ISO 20022 compliant business models for exchange of information for financial services. The mission of the RMG is to ensure that ISO 20022 is a trusted standard providing high quality business models for exchange of information for financial services. The RMG supervises the overall registration process, including the performance of the other registration bodies. It defines the scope of necessary SEGs and acts as a "court of appeal" in case of conflicts between the RA, the TSG, the SEGs and the Submitting Organizations (that is, the standards initiatives that want to use the ISO 20022 standard to develop ISO 20022 messages). It approves the business justifications for development of new messages and the applications of candidate ISO 20022 Member Entities. It also gives an expert opinion on the business and operational impact of any change request that would be received by ISO to amend the ISO 20022 standard.

The RMG had its inaugural meeting in January 2005. The current RMG composition, including the convener, vice convener and secretary is available from the RMG Member List


What is the role of the ISO 20022 Standards Evaluation Groups (SEGs)?

The SEGs, composed of industry experts in specific business domains of the financial industry, have a twofold role: (1) to ensure that the proper industry groups are informed of proposed developments to ensure all business requirements will be addressed, and (2) to validate the new messages from a business perspective to ensure that what will be posted in the ISO 20022 repository by the RA really addresses the needs of future communities of users as described in the business justification accepted by the RMG in the first place.

The RMG has already defined the scope of the following SEGs: ‘Payments’ and ‘Securities’ were created in 2005,'Trade Services' and 'FX' (Foreign Exchange) were created in 2006, 'Cards and related retail financial services' was created in 2008, a Derivatives SubSEG, which works within and reports to the Securities SEG, was created in 2016. If required, additional SEGs can be created by the RMG to address other areas of the financial industry.


What is the role of the ISO 20022 Registration Authority (RA)?

The RA is the guardian of the ISO 20022 financial repository which contains the Data Dictionary with all business and message components, and the Business Process Catalogue with the business areas, message models and derived XML or ASN.1 message schemas. The RA’s mission is (1) to ensure compliance of developed messages with the approved technical specifications, (2) to generate the official message documentation and schemas, and (3) to publish the financial repository and maintain on behalf of ISO. The RA is advised by the RMG or the SEGs. SWIFT has been appointed by ISO as the ISO 20022 Registration Authority.

The ISO 20022 Registration Authority can be contacted at:


What is the role of the ISO 20022 Technical Support Group (TSG)?

The TSG provides technical support to the other ISO 20022 registration bodies (RMG, RA, SEGs) and the submitting organizations or communities of users, upon their request. Requests to the TSG must be sent to the TSG convenor, vice convenor and secretary by e-mail and clearly indicate the nature of the technical issue, and the advice required from the TSG. The current TSG composition, including the convener, vice convener and secretary, is available from the TSG Member List.


How to become a member of the RMG, SEGs or TSG?

Membership of the ISO 20022 Registration Bodies - that is, the RMG, SEGs and TSG -  is open to any entity that has an interest to participate so long as that entity fulfils the criteria of membership described in the Membership page. Existing RMG Member Entities may nominate new experts to the RMG, SEGs and TSG by informing the ISO 20022 Registration Authority at


What is ASN.1?

ASN.1 (Abstract Syntax Notation One) is a data specification and encoding technology jointly standardized by ISO, IEC (International Electrotechnical Commission), and ITU (International Telecommunication Union), and widely used across several industries (cellular telephony, signaling, network management, Directory, Public Key Infrastructure, videoconferencing, aeronautics, Intelligent Transportation, and so on).

ASN.1 is:

  • a formal notation for specifying the logical structure of data that is to be exchanged between two endpoints; and
  • several standard sets of encoding rules for encoding data whose logical structure is specified in ASN.1 notation.

The ASN.1 notation is used to create ASN.1 schemas, which are text files containing the definition of one or more message types of arbitrary complexity. An instance of a message type is encoded using one of the standard sets of ASN.1 encoding rules (DER, PER, OER, XER, etc.) for the purpose of transmission.

The tool that is used by the Registration Authority (RA) to convert the ISO 20022 message models into ASN.1 schemas has been built by OSS Nokalva, Inc. More information about the use of ASN.1 can be found on the OSS website at


What is the difference between a ‘candidate ISO 20022 message’ and a ‘ISO 20022 message’?

Once the RMG has approved the development of a set of messages, these messages can be referred to as 'candidate ISO 20022 messages'. They will keep this name during the development and until they are reviewed and approved by the SEG(s) for publication in the financial repository. They then become 'ISO 20022 messages' (a synonym of 'ISO 20022 compliant messages').

A candidate message that is rejected by the SEG(s) cannot be called a ‘ISO 20022 message’, nor can it any longer be called a 'candidate ISO 20022 message'.


What were the first ISO 20022 messages?

On 14 September 2005, the Payments SEG approved a set of four Customer to Bank Payment Initiation messages as the first ISO 20022 compliant messages.


Who can propose ‘candidate ISO 20022 messages’?

Any community of users or organization can use the ISO 20022 recipe to develop 'candidate ISO 20022 messages'. The registration process is described on this website.


What character encoding is supported by ISO 20022 XML?

The ISO 20022 standard uses XML 1.0. XML 1.0 supports UTF-8, UTF-16 and many more. ISO 20022 has decided to restrict to only UTF-8 based on the fact that it is the most efficient (length-wise) way to transport characters. UTF-16 always requires 2 bytes, UTF-8 uses for the most common characters (such as Basic Latin) only a single byte. Only for exotic characters UTF-8 becomes lengthier, but these characters are rarely required in ISO 20022 messages.


What is the difference between a 'message' and a 'message definition'?

The message definition is the message format while the message is the instance of the message format which is actually transmitted on the wire. On this website, the term 'message' is often used to designate both the message format and the message instance.


What's the difference between a MUG (Message Usage Guide) and a MIG (Message Implementation Guide)?

A MUG is an ISO 20022 document that complements the ISO 20022 Message Definition Report (MDR) when there is a need for further explanation about how to use the message definition(s) in compliance with the standard. MDRs and MUGs are published in the Catalogue of ISO 20022 messages.

A MIG is a document describing the specific way of using ISO 20022 message(s) in a particular context, usually by a specific community of users. MIGs are not official ISO 20022 documents. There is one MUG per message definition while there can be many MIGs. All MIGs are expected to fully comply with the related MDR and MUG. For more information about MDR, MUG and MIGs, download the description prepared by the RMG and the Documentation Clarity Matrix.


Is it possible get an ISO 20022 compliance certification for my implementation?

There is no official certification authority for ISO 20022, and the implementation of ISO 20022 message definitions will depend a lot on the specific requirements of the community that is implementing. The ISO 20022 Registration Authority (RA) and Technical Support Group (TSG) have defined an ISO 20022 Compliance Checklist providing guidance to implementers about some key aspects to be considered in order to be as compliant as possible with the standard. The checklist can be used by implementers, adopters (consultants, tool providers, service providers, etc.), and consumers of ISO 20022 messages to tick whether they have considered each of the key aspects related to ISO 20022 compliance.