The end of coexistence between MT messages and ISO 20022 does not conclude the CBPR+ program. It marks the beginning or a more demanding phase – one defined by stricter validations, lower error tolerance and growing dependence on high-quality structured data.
By the end of November 2025, 80% of daily Swift traffic was already using ISO 20022 format, with more than 2.1 million payment messages exchanged daily across 210+ countries. The migration deadline has passed but the work is not finished.
ISO 20022 is no longer a one-time migration project. It is becoming a permanent operational capability that will shape interbank payments, corporate payments, investigations, reporting, and data management.
As of November 2025, all FI-to-FI payments must be delivered in ISO 20022 format. MT messages are now subject to enhanced FIN validation rules, and non-compliant messages may be rejected or aborted – even after the initial ACK.
Swift has activated contingency processing to convert some MT messages to ISO 20022, but only as a temporary measure. This comes with additional costs, potential data loss, and lower STP rates. Certain MT message types will not be eligible for conversion and will be rejected outright.
In practice, minor format issues such as misformatted account identifiers and incomplete party fields are enough to trigger automatic rejections. Institutions that continue to rely on MT formats face a material increase in operational risk.
The impact extends beyond interbank traffic. From November 2026, Swift will progressively retire MT101 messages used for customer-initiated payments.
This requires banks to review commercial agreements, testing frameworks, and system readiness for pain.001 processing. Corporate clients will also need to align their ERP and TMS platforms with ISO 20022 standards.
ISO 20022 is increasingly a shared transformation that reaches beyond the payments team into onboarding, cash management, and the treasury experience for corporate clients.
With Swift SR 2025, the Hybrid Postal Address format is introduced. During the transition period (Nov 2025 – Nov 2026), multiple formats will coexist. From November 2026 onwards, unstructured-only addresses will be rejected.
This creates an immediate need for data cleansing, enrichment, and changes to customer onboarding and master data processes. Poor address quality will not only create formatting errors – it will directly impact AML screening, sanctions controls and downstream risk management.
Exceptions & Investigations are migrating fully to ISO 20022 formats, including camt.029, camt.056, camt.110, and camt.111. Swift is promoting Case Management 2.0 on FINplus, replacing free-format bilateral investigation flows with structured, traceable messaging.
By November 2026, all institutions must be able to receive camt.110 investigation requests. Full send-and-receive capability with MT messages for E&I retired and no in-flow translation available is required by November 2027.For operations teams, this means redesigning internal workflows and ensuring consistent end-to-end case management aligned with ISO data models.
In later phases, Swift will retire MT messages for reporting, charges, and direct debits, replacing them with ISO formats such as camt.052, camt.053, camt.054, camt.105, and camt.106. No automatic conversion will be provided.
Institutions must be ready to receive and reconcile ISO 20022 reporting messages by November 2027, and should begin coordinating bilaterally with counterparties now.
To reduce risk and control costs, institutions should:
The end of coexistence marks the beginning of sustained operational discipline. Data quality, validation control, and architectural readiness will determine whether institutions can operate efficiently in an increasingly regulated environment.
Institutions that adapt early and build ISO 20022 readiness as a continuous capability will reduce reprocessing costs, avoid the operational disruption and maintain higher STP rates that come with each new Swift milestone.
Want to explore how your institution can improve visibility and operational control across ISO 20022 migration and payments processing? Learn more about ECS Fin’s payment processing solutions or contact our team to schedule a demo.
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