Last reviewed: · Curated by Ohmyfin Organisation editorial.
A UETR (Unique End-to-end Transaction Reference) is the 36-character UUID that SWIFT GPI uses to track a payment from sender to beneficiary. A TRN (Transaction Reference Number) is the bank-internal reference each bank assigns to its own copy of the payment.
Details
The UETR stays the same as the payment passes through every bank in the chain. The TRN changes at every bank — the sending bank, each correspondent, and the beneficiary bank all assign their own TRN.
For cross-bank tracking, only the UETR works. For looking up a payment inside one specific bank, the TRN is sufficient.
On an MT103: UETR is field 121 (mandatory). TRN is field 20 (Sender's Reference).
At-a-glance comparison
UETR vs TRN — side-by-side comparison
UETR
TRN
Length
36 chars (UUID)
Variable (≤16 typical)
Scope
Global — same at every bank
Bank-local — changes at every hop
Mandatory since
2018 (every SWIFT payment)
Always (legacy reference)
MT103 field
121
20
Use for
End-to-end tracking
Single-bank lookup
Shareable with beneficiary
Yes
Only the beneficiary-bank TRN
Key facts
UETR: 36 characters, global, same at every bank
TRN: variable, bank-specific, changes at every hop
UETR is required since 2018 on every SWIFT payment
Ohmyfin accepts either as input
Frequently asked questions
Which one should I share with my beneficiary?
The UETR — it is the same code their bank will see.
Related — more from payment system comparisons and beyond
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