Last reviewed: · Curated by Ohmyfin Organisation editorial.
Field 121 is the UETR (Unique End-to-end Transaction Reference) inside block 3 of every SWIFT message. Mandatory since November 2018. 36 characters in 8-4-4-4-12 hexadecimal format.
How an MT103 maps to the UETR (field 121), sender reference (field 20), value-date/currency/amount (field 32A) and beneficiary details. Source: SWIFT MT103 specification.
Details
The UETR travels with the payment through every correspondent bank in the chain. It is the key Ohmyfin uses to look up the latest available SWIFT payment status.
Quick facts
SWIFT field specification
Example value
:121:12345678-1234-4abc-9def-1234567890ab
Valid characters / format
36-char UUID v4 hex 8-4-4-4-12
Required on MT103
Mandatory
Required on MT202
Mandatory
Required on pacs.008
Mandatory
Notes
UETR. Mandatory since November 2018 — primary tracking key on GPI / pacs.002.
Key facts
Mandatory on every SWIFT payment since 2018
36-character UUID v4 format (8-4-4-4-12)
Lives in block 3 of the MT message
Powers SWIFT GPI end-to-end tracking
Frequently asked questions
How do I extract the UETR from a SWIFT message?
Look inside block 3 (User Header) for the tag {121:...}.
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