Why is my instruction NMAT with no reason code?

Many CSDs only report that no match was found, without saying which field differs. Ask the account servicer for the counterparty’s allegement and compare it with your instruction field by field.

How long can an instruction stay unmatched?

It depends on the market. In T2S an unmatched instruction is cancelled after 20 business days from the intended settlement date or its last status change. Other CSDs have their own rules.

Do the settlement amounts have to be identical to match?

Not always. T2S allows EUR 2 difference for amounts up to EUR 100,000 and EUR 25 above that. Outside the tolerance you get NMAT, often with reason DMON.

Settlement status codes

NMAT: Unmatched

Written and maintained by ZagTrader. Last reviewed 21 October 2026. How this page is sourced and checked

NMAT means the market has not found a counterparty instruction that agrees with yours. Until it matches, the instruction cannot settle.

Code: NMAT
Kind: Status (25D)
Qualifiers: MTCH, INMH

What NMAT means

:25D::MTCH//NMAT is the most common problem status in settlement. Either the counterparty has not instructed yet, or it has instructed with details that differ from yours in at least one matching field.

The :24B::NMAT// reason narrows it down. CMIS means no counterparty instruction was found at all. Disagreement codes name the field: DDAT (settlement date), DTRD (trade date), DQUA (quantity), DMON (settlement amount), DSEC (security), DELN (direction), ICAG (agent), SAFE (account) and others. NMAS means matching has not started yet.

Many CSDs do not tell you which field differs. Austraclear, for example, documents that it sends no NMAT reason codes. In that case compare the allegement (MT578 or sese.028) with your instruction.

Matching does not need every field to be identical. In T2S the settlement amount may differ by up to EUR 2 for amounts up to EUR 100,000 and EUR 25 above that (Clearstream T2S settlement process).

When you see it

Right after a new instruction, before the counterparty has instructed. This is normal and usually clears within hours.
Persistently, when the two sides booked the trade differently: wrong settlement date, quantity in units against nominal, a price or amount difference, or the wrong agent or account.
In T2S markets an instruction that stays unmatched is cancelled after 20 business days from its intended settlement date or last status change.

What to do next

Read the :24B::NMAT// reason. If there is none, ask the servicer for the counterparty’s allegement.
Compare field by field with the counterparty’s view: trade date, settlement date, ISIN, quantity and its type (UNIT or FAMT), settlement amount and currency, direction, payment type (free or against payment), delivering and receiving agents and the place of settlement.
Call the counterparty or their custodian with the common reference or trade details. The side whose data is wrong cancels and re-instructs.
Watch the clock: an instruction still unmatched at the market cut-off misses its intended settlement date. See why a settlement instruction stays unmatched.

Where it appears in MT and ISO 20022

MT (ISO 15022)

MT548 sequence A2, :25D::MTCH//NMAT (or :25D::INMH//NMAT for inferred matching)
MT548 sequence A2a, :24B::NMAT//<reason>, for example :24B::NMAT//CMIS, plus optional :70D::REAS//
MT537 sequence B or C3, :25D::MTCH//NMAT, with reasons in B1 or C3a

MX (ISO 20022)

sese.024 MtchgSts/Umtchd, with NoSpcfdRsn = NORE or Rsn/Cd/Cd = the unmatched reason (UnmatchedReason11Code in sese.024.001.12)
Inferred matching: sese.024 IfrrdMtchgSts/Umtchd/Rsn/Cd/Cd

Questions

Why is my instruction NMAT with no reason code?: Many CSDs only report that no match was found, without saying which field differs. Ask the account servicer for the counterparty’s allegement and compare it with your instruction field by field.
How long can an instruction stay unmatched?: It depends on the market. In T2S an unmatched instruction is cancelled after 20 business days from the intended settlement date or its last status change. Other CSDs have their own rules.
Do the settlement amounts have to be identical to match?: Not always. T2S allows EUR 2 difference for amounts up to EUR 100,000 and EUR 25 above that. Outside the tolerance you get NMAT, often with reason DMON.