Frequently Asked Questions

General

How is AST going to engage with the industry on derivatives?

See section 8 on page 23 of the final report

What is the plan regarding BACS? A lot of Unit Trusts use BACS to settle redemptions and BACS is T+2/T+3

Concerns about the BACS 3 day clearing period were laid out in ENV12 on page 41 of our final implementation plan: https://acceleratedsettlement.co.uk/wp-content/uploads/2025/02/AST-Final-report-Feb-202581.pdf

We are currently finalising the workstreams to carry out further work such as this. Progress will be reported as part of our regular update cycle to industry.

Will the removal of paper share certificates, following the publication of the UK’s Digitisation Report, have any impact on the transition to T+1 settlement?

The dematerialisation requirement from EU CSDR, Article 76(2), was not transposed into UK CSDR. The AST considers that the only UK CSDR amendment needed for the implementation of T+1 settlement in the UK is to Article 5(2). Article 5(2) pertains to shares traded on UK trading venues and does not directly affect the transfer of share certificates, which are typically not traded on trading venues.

Which trade/ transactional scenarios should be confirmed today as per UK Regulation?

This is a question that participants should ask their compliance department. The Taskforce’s view is that everything you confirm today, needs to be confirmed tomorrow.

The Implementation Plan refers to "Electronically using a recognised industry standard and corresponding data dictionary" - What are these data dictionaries and who will provide guidance on them?

The workstreams discussed industry standards in terms of protocols, models and platforms. Protocols include: ISO 15022 (MT messaging); ISO 20022 (MX messaging) and Financial Information eXchange (FIX) messaging. Models cited include: Common Domain Models (CDM). Platforms include: participant and market infrastructure-owned platforms. The consensus was that industry standards are either maintained by industry association / registry body (e.g. ISO, ISDA, ICMA, ISLA, ISITC, SMPG) or by the platform provider themselves.

Discussions also identified that new standards are anticipated for example as part of digitisation initiatives. In summary, the response to the question is that data dictionaries and guidance for a recognised industry standard are provided by your industry association, market practice group, registry body or the platform provider.

I was concerned to see the percentage of respondents to the ValueExchange survey who do not think they need to do anything. Does the AST need to step up education? Or work with participants to educate?

From the start, the AST leadership and its members have been clear about the need to automate and the need to build automation capabilities as soon as possible. Equally, the AST has been clear that a powerful communication tool is the cascade of information from the AST to AST members to tell their clients and for those clients to tell their clients and so on.

The AST presents at multiple industry events and events hosted by market participants for their clients as well as distributing information via quarterly reports, a dedicated T+1 LinkedIn page, interviews and thought pieces in the trade press. These are all designed to provide space to discuss T+1 progress and developments and raise awareness of the need for preparation.

The AST also has a dedicated website, acceleratedsettlement.co.uk, which hosts an FAQs page where market participants can submit any question on any topic related to T+1 or to the AST and then displays our answers to these questions. The website has an events calendar to highlight the various events at which a member of AST will be speaking and also include registration details for these events where applicable.

AST is always looking for new ways of engaging with the market and recently established a quarterly implementation forum which kicked off in June and serves as a further forum to answer questions to help the market with implementation.

We would be very happy to receive new ideas to increase the flow of information.

How do you secure alignment with Europe and Switzerland?

Alignment has been secured and a testing plan covering all three jurisdictions has been published. You can find the testing plan here

What is the market practice for debt new issuance? (SETT11a)

Debt new issuance is not subject to T+1. However, once admitted into trading, it becomes eligible for settlement on T+1.

Is email a recognised method to communicate allocation data between participants?

A core focus of the industry guidance is committment to automation. Whilst the use of email represents a method of electronic communication, the term ‘email’ does not stipulate the content and or structure of the data that is communicated.

Usually, the use of ‘email’ infers a manual process, or manual activities. However, it is understood that some participants offer automation related to data sent via email where a counterparty can facilitate straight through processing using corresponding structured data. This scenario which includes ‘email’ could be deemed an acceptable method between counterparties. In summary, the consensus is that email is not a recommended method. However, certain participants may support or tolerate its usage as long as it is automated as part of straight through processing.

What are the biggest challenges to implementation?

There are 2 principal challenges. Communication and automation and all firms have a role to play in helping address each.

1. Communication: Everyone needs to know about the move to T+1 and even today, we should not assume that everyone does. Given that each participant is a single link in a post-trade chain, all of which needs to be able to operate efficiently and in compliance with T+1 reduced timeframes, each participant should not only be working on their own compliance, but also discussing the compliance capabilities of their upstream and downstream partners. If everyone is aware of what needs to be done, we will collectively find compliance easier. Passing problems down the chain simply makes it harder for everyone in the chain to meet the target.

2. Automation: The continuing thread from launch of the Implementation Plan in February 2025 until now is the need for automation. The loss of 80% of today’s processing time leaves a very short time for exception management and so reducing the number of exceptions is critical. This is achieved by automation to ensure the correct data is in the correct place at the correct time. Post go-live research in the US revealed that firms that failed to automate experienced anything up to an 18% increase in their back-office staffing costs. This is not a sustainable solution.

What is the AST view on T0, tokenisation, implementation of DLT based solutions etc?

It is clear that the global direction of travel in post-trade is towards the implementation of shorter settlement cycles for all the cost and risk reduction reasons identified when originally looking at T+1. As a result, it is safe to say that T+1 is in reality, a stop along the way to T0 and increased flexibility in post-trade processing that will be enabled by digitalisation.

At this point, the when and the what of the potential end state of global markets generally and post-trade processing specifically is not yet clear. However, one fact that is already known is that future markets will rely heavily on automation and automation of processes now will provide long term benefit in terms of future proofing participant systems.

The level to which a participant will need to automate will be determined by the current level of automation, or not, that any particular participant has already implemented. So the AST is not in a position to speculate as to how specific participants will need to prepare for T+1 or beyond.

What is the impact on APAC investors?

APAC investors are an important component of the total capital investment into the UK and for this reason, supported by the flexibility of the UK settlement system CREST, we have been able to specify the key deadline of matched instruction delivery to CREST with a deadline that allows APAC investors time to address any settlement instruction issues. The T+1 instruction deadline is UK 05.59 on T+1, which is 2.00pm on T+1 in Japan, 4pm in Australia etc giving these participants, we believe, time to complete their instruction processing.

What are the benefits beyond compliance?

As the implication of compliance is increased automation either through internal process enhancement or outsourcing, the expectation is that processing marginal cost will drop through volume and efficiency increases. We also anticipate a reduction in capital tied up as collateral, similar to that experienced in the US. The Bank of England has estimated this to be as much as £1bn. The final benefit is that the future of capital markets lies with digitalisation and the basis of digitalisation will be automation, so T+1 is starting to lay the groundwork.

How is any actual measure of market readiness due to be achieved in order to have confidence that the burden of readiness is not simply sitting with a handful of the largest market participants?

This is entirely about communication and collaboration. For communication, we are speaking with all constituencies and participants on a daily basis and we have two engagement surveys per year where we ask questions of firms to share their readiness, as well as ongoing and more frequent surveys of Infrastructures and Global Custodians on the various AST recommendations. The AST is also working closely with the authorities to share and discuss feedback on levels of preparedness in order to determine where additional focus might be required.

Scope

What convention should apply to securities listed in multiple venues in different jurisdictions?

The matrix in the AST Technical Group report (pg.23-25) lays out all the different permutations that need to be considered, including where market conventions apply. As a general rule, for securities listed on trading venues in non-UK jurisdictions, the settlement cycle convention should be relative to the final settlement location.

Will T+1 be the standard for physical deliveries resulting out of UK stock options?

Generally speaking, yes, we expect this to be the case as T+1 becomes the standard settlement cycle across the UK as of 11 Oct 2027. However, further analysis is still required regarding the impact to the listed derivative workflow.

Will testing windows be defined?

Testing windows have been defined in the T+1 testing plan that was published in March 2026. You can find the testing plan here

Settlement

Can you explain how you arrived at the 5:59am deadline?

The AST Settlement workstream looked in detail at the instruction cut off times. Today, the expectation is that fully matched instructions will be input into CREST by 20.00 UK time on T. As part of the migration to T+1, CREST will extend this deadline to 21.00 and the expectation is that UK domiciled participants will adhere to this deadline.

In recognition of the fact that international investors are critical to the UK market, we also identified a second instruction deadline to enable such investors, particularly those in APAC to have time to complete their settlement requirements during local working hours. This led to the creation of the 05:59 UK time on T+1 instruction deadline, intended for use only by non-UK domiciled market participants.

For Broker-to-Broker flow of in-scope instruments where allocations and confirmations are not carried out, how does SETT 01 apply?

SETT01 does not apply to transactions where participants are not required to allocate or confirm today. However, UK AST would recommend that you perform a reconciliation of your transactions to ensure that you are allocating and confirming appropriately with your clients and counterparts.

What if my counterparty won’t comply with SETT 01 e.g. what if they are unable to confirm electronically? Must I stop doing in-scope business with them or am I able to track them/ follow up with them/ encourage them to comply?

The code of conduct, as defined by market participants during the recommendation development phase, sets out a series of expectations of all market participants. As laid out in our kick-off event on 20 February 2025 by the FCA, the expectation is that all market participants will comply with these recommendations, especially the twelve identified as critical which includes SETT 01.

We expect that all market participants will reflect on this guidance and endeavour to comply with these recommendations in order to increase the overall operational efficiency of UK markets. In this regard, the support of participants in informing and educating their counterparties on this requirement would be welcome.

For prime brokerage clients that provide instructions late on T+0, what is the UK industry guidance on how to deal with this if the client is unable to meet the cut-off time?

What happens at CREST if my instruction is late, i.e submitted after 05:59 am on intended settlement date?

Settlement instructions submitted after the 05:59 deadline that match ones from counterparts (i.e. are input second) will be subject to CREST’s matching discipline but will still be assessed for settlement.

What is auto-shaping? Can you please explain? Also, what is the difference between auto-shaping and auto-partialling?

Auto-shaping and auto-partialling/splitting are two separate functions that occur at different points in the transaction life cycle. Auto-shaping occurs before or as the transaction is input into the settlement system, whilst auto-partialling/splitting typically occurs after the transaction has been matched. Both are viewed as improving settlement efficiency.

Auto-shaping is the ‘breaking down’ of a single large trade into smaller, pre-agreed, standard-sized settlement instructions (‘shapes’) that are sent into the settlement system for matching and settlement. This is typically used in fixed-income transactions. Therefore, a large trade of £150 million could be ‘shaped’ into three instructions to the settlement system of £50 million each. This ‘shaping’ reduces the liquidity/credit requirement for the settlement of each ‘shaped’ transaction and increases the flow of the security around the settlement system, maximising the amount of settlement that occurs and improving settlement efficiency.

In contrast, auto-partialling or splitting is the process of dividing a single matched transaction where there are insufficient securities available to settle the transaction. The single transaction can be partialled/split into a portion that can settle using the available resources. The unsettled portion will settle or be further partialled/split in the future as resources become available.

The use of partialling/splitting increases the liquidity of securities within the settlement system by maximising the amount of settlement that occurs, improving settlement efficiency.

What are the consequences of trade failure?

There are 3 consequences: Expect closer scrutiny from the regulatory authorities if your firm is habitual and high-level failing organisation. There are also financial penalties imposed by CREST related to delays in submitting instructions and/or failure of trades. The size of the fine is specified in the CREST rules and is proportionate to size and length of delay/fail. And finally, there will be Reputational issues if you are, again, a habitual trade ‘failer’, given the earlier penalties might be shared with your counterparty.

Corporate actions

What do we mean by ‘all UK trading venues’? Is it regulated markets or does it include MTF, Systemic Internalisers etc (COAC1a/b)?

Regarding CoAc 1a/b, it was agreed that the scope should cover UK Trading Venues only. MTFs and Systemic Internalisers base corporate action entitlement on the key event dates, which are driven by the rules set by exchanges on issuers.

Will there be any changes to dividend claim processing at CSD level?

The CSD currently generates claims for 5 days post record date. The working group recommends this should not be condensed considering the shortened settlement cycle.

What is the standardised dividend procedure which is noted in COAC 01a and COAC 01b?

The ‘standardised dividend procedure’ referenced sets out standards for dividend announcement, structure and timetable for securities listed on the London Stock Exchange. These procedures are updated annually and can be found HERE. The AST recommended that this procedure be adopted by all UK trading venues (as defined by the FCA).

What will the relationship be between the Ex Date and Record Date in a T+1 Environment?

Post implementation of T+1, entitlement will still be driven by transactions instructed before ex-date. As a result, the ex-date and record date will converge to the same day, remaining consistent with the default T+1 settlement cycle. This approach is consistent with the US (trading on a T+1 basis since May 2024) and with plans in the European Union and Switzerland (October 2027).

What will be the impact on distribution events in the UK Market under T+1?

Distribution of Rights/Open Offer Entitlements – In both cases, the Record Date precedes Ex Date. Settled positions on Record Date are credited with open transactions generating market claims. The working group found that the current timetable was adequate in a T+1 environment.

What will be the impact on Stock Outturn events such as Bonus Issues / Spin Off Events in the UK Market under T+1?

Entitlement will be based on positions traded prior to Ex/Record Date. Unsettled transactions will generate claims as normal within the CREST system. For the avoidance of doubt, post T+1, Ex date and record date will merge to be the same date.

Will there be any changes to the CREST Transformation process considering T+1 Settlement?

No — the AST recommends that the current 10 business days be maintained.

Proposal: Euroclear UK & International (EUI) has reviewed the transformation process in the CREST system and confirmed that there will be no changes prior to 11 October 2027. Following this, any changes will be consulted with the market, for example, any proposed changes to the 10 business day election period for right issues

Will there be any change to the buyer protection or market deadlines for the UK Market under T+1?

The AST appreciate the criticality of time in the processing of voluntary corporate actions. We continue to challenge the status quo and are working with registrars, the CSD and other stakeholders to maximise potential opportunities to improve buyer protection. Further updates will be published on the CSD website and communicated via the market.

How will the voluntary processing team have visibility to trades booked on deadline date -1? Our processing window is going to shrink significantly.

The taskforce acknowledges that accelerated settlement will condense the processing window for voluntary corporate action teams. In terms of trade visibility, trade aggregation occurs after the trading day, meaning that participants may not see their traded balances until AM on Market Deadline. The actions of the AST to explore more competitive deadlines (both market and buyer protection) is in direct response to this challenge.

How are market claims going to be managed on the back of ex date / record date trades? Will ex date and record date be the same date now?

Ex and Record Date will converge which reflects the approach taken by the EU and United States. Claims within CREST will continue to be automated, with no change to the current transformation logic used in the system. There will also be no reduction of the current claims generation period of 5 days, or transformation period of 10 business days

On voluntary corporate action events - will there be any changes to deadlines? Currently we have early morning deadlines in the Nordic market and UK market, specifically concerning rights issues and tender events. Has the DVP settlement window been confirmed? Will there be any automation on claims/ broker protections from CSDs?

The AST fully endorses a more competitive deadline in the UK Market for Voluntary (with the exception of rights issues which trade T+1 today) and Mandatory with Options events. We are actively engaging with registrars to understand their processes and working to a solution where an enhanced deadline can be agreed. The UK market already has automated claims and a mechanism to lodge broker protections. There is no announced change to the current DVP settlement window which closes at 15:45 within the CREST System.

Current deadline of 11 am on ISD to input buyer protection on failing trades may be tight for participants to reach. What is being done to review this deadline and potentially push it out further by few hours?

A proposal is currently being considered to move the buyer protection deadline to Market Deadline Day.

Trading and liquidity

If the UK gets an SFT exemption and the EU does not, what complexities do you foresee?

Both the EU and UK have determined that SFTs are exempt. For the UK, you can find the draft SI published by HMT here

What is being done about the fund management creation and redemption/cash cycle misalignment - it is current market practice for this to be T+3 vs T+2 for the underlying equity. What will happen post T+1?

In May 2025, the IA, PIMFA and AIMA published a joint recommendation to the industry that post T+1, the participants align their creation/redemption timeframes on a T+2 cycle to allow greater alignment with the T+1 equity settlement cycle. It is now the responsibility of the industry participants to adopt and implement this market practice. You can find the market practice here

Stock lending

What is the industry stance on the future state of SLOs and the subsequent creation of the SLRs in CREST (i.e., are they looking to move the SLR creation to the same day as the SLO) as some people today can use the DEL transaction type to return the stock same day if required?

The full detail of the current status of SLO/SLR market practice proposals was published by ISLA on their website on 30/10/2025 and can be found here.

For convenience, we have summarised it below:

By June 2026, ISLA are aiming to update industry market practice supported by any necessary CREST process and procedural change, to allow same day (T0) Stock Loan Opens (SLOs) and Stock Loan Returns (SLRs) including collateral movements where both lender and borrower agree.

Under this new approach, CREST will still create the SLR when the SLO settles, but same-day returns will not settle automatically. Instead, they will default to priority for both Lender and Borrower, whereby both parties must agree to manually raise the priority to approve same day settlement. On T+1, CREST priorities will reset to normal levels.

Operationally, same-day returns will not resolve existing billing accrual challenges since most systems calculate fees on end-of-day positions. Lenders may therefore need system changes or manual workarounds for intraday accruals as a result.

Collateral transactions will continue using the same SLO/SLR types for now, with new transaction codes CLD (Collateral Deliver) and CLR (Collateral Received) to support same-day collateral returns under “CREST 2.”

Borrowers will not be able to unilaterally trigger same-day returns, they will require lender authorisation. Triparty agents have already reviewed the system changes necessary to support these workflows.

Overall, the change aims to support same-day settlement for underlying borrows, loans and collateral movements, maintain lender control, and modernise CREST stock loan and collateral operations ahead of the Q2 2026 go-live.

The use of DEL for SLOs and SLRs is not recommended by either ISLA or CREST.

If agent lenders instruct sale transactions into the market after the T+1 05:59am deadline set by the AST T+1 recommendation Set 02:00, would they be in breach of the code of conduct?

Yes. However:

If a lender (including lending agents / lending intermediaries) instructs a loan with a zero priority and the borrower matches their instruction, CREST will not settle the trade until the lender raises the transaction priority above zero.
This uses the existing CREST ‘hold and release’ functionality to allow lenders agents/intermediaries to send instructions in compliance with the code of conduct 05:59am on T+1 deadline.

Why might agent lenders struggle to release settlement instructions to CREST by 05:59am on T+1 actual settlement date?

Several reasons contribute to this challenge:

Omnibus Structured Account Setup: Agent lenders operating omnibus accounts must ensure that underlying beneficial owners have sufficient settled holdings before releasing delivery instructions. This dependency can delay trade release.
Late Sale Notifications: Sales that trigger securities recalls may be communicated late in the day, especially in markets with concentrated end-of-day liquidity. This leaves limited time to issue timely recalls and process returns.
Early Cut-off Time: The 05:59am cut-off time falls outside standard operating hours for many agent lending platforms and service providers, increasing reliance on automation and exception-based processing.
Asset Reallocation: Generally, client sales of assets on loan are resolved through reallocation of loans (e.g., to other lending clients). Where reallocation is not possible, delivery cannot proceed.

Is this the end of sec lending at its current levels?

Securities are borrowed to support short selling, to source collateral, and to prevent or resolve settlement failures; none of these fundamental drivers disappear with T+1. Trading and collateral-driven borrowing should continue broadly unchanged, while the compressed settlement window may actually increase borrowing to avoid fails and fail-funding costs as firms adapt their processes. Over time, greater automation and inventory management are expected to support stable or higher lending activity rather than a structural decline.

The point that needs clarifying is to what extent we should make preparations to facilitate timely recalls. For example, we do not actively lend government bonds or other securities (repo or otherwise). However, our PB agreement allows rehypothecation of the securities we custody. We have no visibility on rehypothecation and so it’s difficult to know in advance if securities are being lent out. We notify our PB on trade date when we have sold a security and match trades in a timely fashion. Are there any other best practices you see that we should align ourselves with on this point?

Where an investment firm does not operate a direct securities lending or repo programme but permits a prime broker to rehypothecate assets, the industry expectations supported by the UK regulator around “preparations to facilitate timely recalls” is met primarily through ensuring that long sales (long inventory position that typically a hedge fund will own outright) can settle on time, even where positions have been rehypothecated.

In this model, the firm’s responsibilities typically include instructing and matching sale trades on trade date; providing the prime broker with prompt, reliable visibility of long sales; and performing oversight to gain comfort that the prime broker’s rehypothecation, inventory management and recall processes are compatible with T+1 settlement of client transactions.

Good practice would generally be to: obtain and periodically review the prime broker’s documented procedures for substituting collateral when a rehypothecated long is sold and for recalling stock lent or repo’d out for its own account; agree operational cut‑off times and escalation paths for late or large sales, including hard‑to‑borrow names; and monitor settlement efficiency to confirm that the prime broker’s arrangements work effectively in practice. In this way, the firm can demonstrate that it has taken reasonable steps to support timely recalls and settlement, consistent with the market’s expectations under T+1.

This is a good example of the interlinked nature of settlement, where your compliance with market practice is dependent on the capability of another party, the PB in this case, and you must therefore be aware of that party’s ability to support your T+1 settlement obligation.

How will the same day stock loan changes affect the UK Triparty providers?

ISLA has discussed the introduction of same‑day stock loan returns (SLRs) in CREST extensively with members, including triparty collateral agents, as part of its accelerated settlement and T+1 workstreams. To date, triparty agents have not identified any material issues that would prevent them from supporting these changes, although individual providers may adopt different operational approaches or timelines.

Further background on same‑day SLRs and related best practice can be found in the ISLA Best Practice Handbook and associated UK T+1 materials on the ISLA website.

Key changes to note include:

CREST will support same‑day settlement of SLRs, rather than deferring returns to the next business day as is currently required.
New control measures mean that same‑day returns require explicit lender approval via priority management in CREST, ensuring that returns only settle where both parties agree.
These enhancements are designed to support the UK’s transition to T+1 while preserving control for lenders and their agents over recall and return flows.

You can find further detail in the relevant sections of the ISLA Best Practice Handbook on stock loan returns and accelerated settlement. SLO/SLRs in CREST – AST UK T+1 FAQ | ISLA Best Practice Handbook – ISLA

What are the impact to recalls, sells and other operational constraints and regulation that may come into play?

The move to T+1 settlement, combined with same‑day stock loan returns in CREST, increases the time‑criticality of recalls and sale notifications and places greater emphasis on automation and straight‑through processing across the securities lending lifecycle.

Key themes include:

Recalls and sale notifications – Market participants are expected to automate recall and return processing and ensure prompt notification of underlying sales so that recalls can be generated, transmitted, and settled within the shortened settlement window.
Cut‑off times and returns – The UK T+1 Implementation Plan and the ISLA Best Practice Handbook highlight recommended market cut‑offs for recalls and returns, aligned as far as possible with local trading hours and settlement deadlines.
Operational controls – Same‑day SLRs in CREST introduce lender approval mechanisms and settlement‑priority controls designed to support both settlement efficiency and risk management.
Regulatory context – These operational practices sit alongside broader regulatory expectations around settlement discipline, SFTR reporting and operational resilience, and are intended to reduce settlement risk in a T+1 environment.

For a detailed, scenario‑based description of recalls, returns, notifications and related operational considerations in both the UK and EU, please refer to the “Recalls, Returns & Notifications” section of the ISLA Best Practice Handbook on the ISLA website. Recalls, Returns & Notifications | ISLA Best Practice Handbook – ISLA

How are market participants, in particular securities lending participants, preparing for T+1 and what are their major concerns at this stage?

For all topics raised please see the ISLA Best Practice handbook as this will give a good insight of each topic that has surfaced under T+1 both in the UK and EU: ISLA Best Practice Handbook | ISLA Best Practice Handbook – ISLA .

Current areas requiring attention are highlighted in industry surveys and working‑group discussions include:

The feasibility of achieving near‑real‑time communication between beneficial owners, agents, borrowers, and brokers for recalls and allocations.
Operational capacity during peak volumes, corporate actions, or market stress, given the reduced time available to resolve exceptions.
Cross‑border impacts where instruments or participants are subject to different transition timelines or settlement regimes (for example, between the UK, EU, US, and Switzerland).

For a consolidated view of securities lending‑related guidance, please refer to the ISLA Best Practice Handbook, which captures member consensus on key T+1 topics across both the UK and EU. For broader, cross‑industry analysis of T+1 preparedness, concerns, and benchmarking metrics, you may also wish to consult the Value Exchange surveys, reports, and webinars on accelerated settlement. Accelerated Settlements and T+1 – Welcome to the ValueExchange

FX

What work are you doing around Foreign Exchange in preparation for T+1? It’s a huge piece that is often an after thought

FX is included with the UK AST Final Report, and we have also published an ‘Expert Series’ webinar and supplementary paper to aid market participants in all jurisdictions with their preparation.