UETR vs TRN: Which Reference Tracks Your International Wire?
The UETR is the global 36-character tracking ID that stays the same at every bank. The TRN is a bank-internal reference that changes at every hop. Track any UETR or payment reference free on Ohmyfin →
Details
The UETR (Unique End-to-end Transaction Reference) was introduced by SWIFT in November 2018 as a mandatory field on all GPI-enabled SWIFT payments. It is a 128-bit UUID formatted as a 36-character hyphenated string (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx), for example: 3b84b5b5-4a3c-4b9e-9fc8-e0c5e8a0b3d2. The UETR is generated by the originating bank when the payment is initiated and is carried unchanged through every SWIFT message in the chain — the MT103, any MT202 COV cover messages, and the pacs.008/pacs.009 successors. Every bank in the chain — the sending bank, each correspondent, and the beneficiary bank — records and processes the same UETR.
The TRN (Transaction Reference Number) is found in field 20 of an MT103 — labelled "Sender's Reference". It is a free-format alphanumeric reference (up to 16 characters) assigned by the bank that generated the message. Critically, the TRN changes at every hop: when the sending bank creates an MT103, it sets its own TRN in field 20. When a correspondent bank passes the message on and creates a new copy of the MT103, it assigns a new TRN in field 20 of its outgoing message. The beneficiary bank sees the TRN of the last correspondent in the chain — not the original TRN from the sending bank. This is why a TRN alone is useless for end-to-end tracing.
Practical consequences for payment investigations: if your wire is delayed and you call your bank, they will give you a TRN (their internal reference). If you call the beneficiary's bank, they will see a completely different TRN. Neither bank can find the other's TRN without manually contacting every correspondent in the chain. The UETR solves this: every bank in the chain can look up the UETR on the SWIFT Tracker and see the full payment journey. When you paste a UETR into Ohmyfin, the tracker returns the latest known status at each bank — without any manual inter-bank communication required.
Where to find the UETR: on an MT103, the UETR is in block 3 field 121 (Unique End-to-end Transaction Reference). On a pacs.008 message, it is in the GrpHdr/UETR XML element. Your bank's online confirmation usually shows it labelled as "UETR", "GPI Reference", or "End-to-end reference". If you cannot find it, call your bank and ask specifically for the "GPI UETR" — every SWIFT GPI payment has one, and your bank is obligated to provide it to you. Some banks also show it on the paper MT103 confirmation if you request one.
UETR vs IMAD/OMAD (US Fedwire): in the US, domestic Fedwire payments use an IMAD (Input Message Accountability Data) and OMAD (Output Message Accountability Data) instead of a UETR. These are Federal Reserve references for the Fedwire leg only — they are not visible across banks the way UETR is. For an inbound international wire to the US that uses both SWIFT and Fedwire, the UETR tracks the SWIFT leg (from the foreign bank to the US correspondent) and the IMAD/OMAD tracks the final Fedwire settlement inside the US. Ohmyfin tracks the SWIFT leg by UETR; the Fedwire leg requires your US bank.
How to use both references: the UETR is the reference to share with anyone outside your bank — your beneficiary, the beneficiary's bank, your lawyer, your correspondent bank relationship manager. It is internationally understood and uniquely identifies the payment. The TRN is the reference to use when speaking with your own bank's back office, because it is the reference in their internal systems. For any end-to-end dispute, investigation, or SWIFT recall (MT192), the UETR is the essential identifier.
At-a-glance 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-character UUID, global, same at every bank in the chain, mandatory since November 2018
- TRN (field 20 on MT103): variable-length, bank-specific, changes at every correspondent hop
- UETR is required for all SWIFT GPI payments — if your MT103 has field 121, it is a UETR
- US Fedwire uses IMAD/OMAD instead of UETR for the domestic settlement leg
- For end-to-end tracing and SWIFT recalls (MT192), always use the UETR
- Ohmyfin accepts UETR or bank reference — paste either for live SWIFT GPI status
Frequently asked questions
Which one should I share with my beneficiary?
Share the UETR — it is the same 36-character reference their bank will see in the SWIFT Tracker. A TRN from your bank is useless to the beneficiary's bank because it changes at every hop.
Where do I find the UETR on my MT103?
The UETR is in MT103 block 3, field 121, labelled "{121:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}". It is a 36-character hyphenated UUID. Ask your bank for "the GPI UETR" or "field 121 of the MT103" if you cannot locate it on your confirmation.
What is the difference between field 20 and field 121 on an MT103?
Field 20 is the Sender's Reference (TRN) — a bank-internal ID assigned by the message sender, up to 16 characters, changes at every hop. Field 121 is the UETR — a globally unique 36-character UUID that stays the same from origination to the beneficiary bank.
My bank gave me a reference that is not 36 characters. Is it a UETR?
No — a UETR is always exactly 36 characters in the format xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx (8-4-4-4-12 groups separated by hyphens). If your reference is shorter or a different format, it is likely the TRN (field 20, up to 16 chars) or a bank-specific booking reference. Ask your bank explicitly for "the GPI UETR" for a cross-border SWIFT wire.
What if my bank says there is no UETR?
If the payment was sent as a SWIFT GPI payment (which all major banks have required since 2018), there must be a UETR. If your bank says there is none, the payment may have been processed on a legacy pre-GPI system (unlikely at a major bank), sent as a domestic transfer rather than international wire, or there may be a communication failure. Request the full MT103 printout and check for field 121.
Can I use the TRN to track a payment on Ohmyfin?
Ohmyfin primarily uses the UETR for SWIFT GPI lookups. Some bank references may be accepted as alternate inputs, but only the UETR provides true end-to-end visibility across all banks in the chain. If you only have a TRN, ask your bank to confirm the associated UETR.
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