What does PEND LACK mean in MT548?

:25D::SETT//PEND with :24B::PEND//LACK means your delivery has not settled because your own account does not hold enough deliverable securities, but settlement on the intended date is still possible. Bring the securities in before the last settlement cycle of the day. See PEND LACK explained.

What is the difference between LACK and CLAC?

LACK means the securities are missing in your account: you are the delivering party and you must fix it. CLAC means the counterparty is delivering to you and its account is short: you can only chase the counterparty.

What is the difference between PEND LACK and PENF LACK?

Same problem, different timing. PEND LACK still allows settlement on the intended date. PENF LACK means that date is lost and the trade is failing, which in the EU starts CSDR cash penalties for each business day the fail lasts.

Settlement status codes

LACK: Lack of Securities

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

LACK tells the account owner that its own safekeeping account does not hold enough deliverable securities for a delivery to settle. The shortfall is on your side, not the counterparty’s.

Code: LACK
Kind: Reason (24B)
Used with: PEND, PENF, PPRC

What LACK means

LACK is reported on a delivery: a MT542 or MT543 in MT, or a delivering sese.023 in ISO 20022. The custodian or CSD checked the position in the safekeeping account and found fewer deliverable securities than the quantity to deliver. When the shortfall is in the counterparty’s account instead, you receive CLAC.

The status in front of it tells you how urgent it is. Under PEND (:24B::PEND//LACK) settlement on the intended settlement date is still possible, so there is time to bring the securities in. Under PENF the instruction is failing: the intended settlement date can no longer be met and every further business day is another fail day. Under PPRC the account servicer has not yet processed the instruction because of the shortfall; some custodians check the position before they pass a delivery on to the local market.

"Deliverable" is the key word. Securities can be on the account and still not count: blocked for a corporate action (SBLO), out on loan (LALO), pledged, or already used by another delivery that settled first. Some servicers report the more precise code, others report LACK for all of these.

When you see it

In an MT548 or sese.024 status advice on the morning of the intended settlement date or after a settlement cycle in which the delivery could not settle, and on every MT537 statement of pending transactions while the shortfall lasts.
Typical causes: a receipt you counted on failed upstream (a back-to-back trade where your purchase did not settle, sometimes reported as LAAW); a short sale not yet covered; loaned securities recalled but not yet returned; securities held in another account or at another custodian; a corporate action that changed the line, for example a new ISIN after a merger or split; an instruction for more than the available position.
In T2S the platform reports LACK from its provision check, and can report it together with another reason in the same sese.024: for a delivery against payment where you lack securities and the counterparty also lacks cash, the reasons are LACK and CMON (ECB T2S multiple-status reporting).

What to do next

You have to act; the counterparty cannot fix a LACK. Compare the instruction quantity with the available position on the safekeeping account (your MT535 or semt.002 statement of holdings) and with the pending receipts on your MT537.
If a receipt that would cover the delivery is pending, chase that receipt first. Most CSDs recycle a failing delivery in later settlement cycles, so it settles once the securities arrive.
If you hold part of the quantity, check whether partial settlement is allowed (:22F::STCO//PART or NPAR in the MT54x instruction, SttlmParams/PrtlSttlmInd in sese.023) and, where the market supports it, agree partial delivery with the counterparty.
Otherwise borrow the securities, recall a loan, or move the position from another account, then tell the counterparty when you expect to deliver.
In the EU, CSDR cash penalties have applied to settlement instructions failing at EU CSDs since 1 February 2022, charged for each business day the fail lasts after the intended settlement date; a delivery failing for lack of securities is normally attributed to the delivering party. Under the CSDR Refit, mandatory buy-ins apply only if the European Commission introduces them by an implementing act. Check your CSD’s daily penalty reports.
More detail: MT548 PEND LACK explained and failing settlement (PENF).

Where it appears in MT and ISO 20022

MT (ISO 15022)

MT548 sequence A2a (REAS), :24B::PEND//LACK, following :25D::SETT//PEND in sequence A2 (STAT).
MT548 sequence A2a, :24B::PENF//LACK, following :25D::SETT//PENF once the instruction is failing.
MT548 sequence A2a, :24B::PPRC//LACK, following :25D::IPRC//PPRC when the servicer holds the instruction back.
MT537 sequence B1 (statement by status) or C3a (statement by transaction), :24B::PEND//LACK or :24B::PENF//LACK.
An optional :70D::REAS// narrative in the same REAS block can say how much is missing.

MX (ISO 20022)

sese.024 SttlmSts/Pdg/Rsn/Cd/Cd = LACK when pending, SttlmSts/Flng/Rsn/Cd/Cd = LACK when failing; free text in SttlmSts/Pdg/Rsn/AddtlRsnInf or SttlmSts/Flng/Rsn/AddtlRsnInf.
sese.024 PrcgSts/PdgPrcg/Rsn/Cd/Cd = LACK for pending processing.

Questions

What does PEND LACK mean in MT548?: :25D::SETT//PEND with :24B::PEND//LACK means your delivery has not settled because your own account does not hold enough deliverable securities, but settlement on the intended date is still possible. Bring the securities in before the last settlement cycle of the day. See PEND LACK explained.
What is the difference between LACK and CLAC?: LACK means the securities are missing in your account: you are the delivering party and you must fix it. CLAC means the counterparty is delivering to you and its account is short: you can only chase the counterparty.
What is the difference between PEND LACK and PENF LACK?: Same problem, different timing. PEND LACK still allows settlement on the intended date. PENF LACK means that date is lost and the trade is failing, which in the EU starts CSDR cash penalties for each business day the fail lasts.