ISO20022: Structured Address Data for Financial Institutions - A necessary change for cleaner data by November 2026

The ISO20022 messaging standard is being adopted across financial services to support more consistent, structured and machine‑readable data exchange.

• For UK financial institutions, including banks, building societies and payment service providers.
• This brings specific changes to how address information must be recorded and transmitted.
• One of the most significant updates is the move away from free‑text address lines towards a fully structured address format.
• From November 2026, ISO20022 messages that contain unstructured address lines will no longer meet the standard.

What's changing?

Many financial systems in use today were designed before structured address data was a priority. As a result, addresses are often captured using open‑ended fields such as:

• Address Line 1: 10 Downing Street 
• Address Line 2: Westminster  
• Town/City: London  
• Postcode: SW1A 2AA  

Under ISO20022, this approach is no longer compliant. Addresses must instead be broken down into clearly defined components, for example:

• Building number: 10
• Street name: Downing Street
• Suburb/locality: Westminster (optional)
• Town: London
• Postcode: SW1A 2AA
• Country: GB

This  ISO20022 structured format:

• Reduces ambiguity, improves routing and compliance checks, and enables richer reporting and analytics.
• Supports regulatory expectations around clearer, more reliable data for cross‑border payments and KYC processes.

A Positive Development, But Not Without Complexity

• This change as a positive step forward. It reflects a wider shift across industries towards better data structure, reduced reliance on loosely formatted inputs, and stronger alignment between operational systems.
• However, that doesn’t mean the work is easy.
• Many UK organisations still rely on unstructured address storage in their internal databases. Even where data is relatively complete, it may lack the field‑level detail required for ISO20022 compliance.

Common challenges include:

• Address lines containing multiple elements (for example, building name, street and locality combined)
• Historical records stored in inconsistent or incomplete formats
• User‑ acing forms that don’t collect address components separately
• Uncertainty around how UK address conventions fit within international standards

In practice, achieving compliance often requires more than reformatting fields.

• It involves parsing, validation, enrichment, and in some cases, rethinking how addresses are captured and maintained across key systems.

SOURCE

https://blog.ideal-postcodes.co.uk/iso20022-a-welcomed-shift-to-structured-address-data-for-financial-institutions