A contemporary accountancy desk at dusk, a task lamp lighting a dark monitor and a keyboard

Accountancy practices

Client onboarding for an accountancy practice: where the hours go

Onboarding looks like a short list of tasks and behaves like a long chain of dependencies. Most of the elapsed time is not work, it is waiting on somebody outside the practice, and nobody owns noticing that the waiting has gone on too long.

Last checked 19 September 2026

What a new name actually sets off #

A new client is not one job. It is a sequence, and several of the steps cannot start until an earlier one finishes. In a practice the sequence usually looks something like this, though the detail depends on the services and on your supervisor:

  1. Establishing who the client is, and who ultimately owns or controls them

  2. Customer due diligence under the Money Laundering Regulations

    Including the risk assessment that decides how much diligence is enough.

  3. An engagement letter setting out scope, and getting it signed

  4. Agent authorisation with HMRC for each service you will act on

  5. Professional clearance where there is an outgoing accountant

  6. Collecting the opening records

    The same chase covered in what chasing clients for records costs.

  7. Setting the client up in whatever systems the practice runs

The compliance steps are not optional and not light #

HMRC guidance on the Money Laundering Regulations describes customer due diligence in a sentence.

taking steps to identify your customers and checking they are who they say they are
GOV.UK, Money Laundering Regulations: your responsibilities

Enhanced due diligence applies in higher risk situations, including customers who are not physically present. The guidance also requires a written policy, a nominated officer, staff training, and records kept for five years beginning from the date a business relationship ends or a transaction is completed.

Supervision itself is a registration obligation. HMRC guidance states that accountancy service providers must register unless they are already supervised by a professional body, and that trading while not registered "is a criminal offence. It may result in a penalty or prosecution". Registration is renewed annually.

For company clients there is now a further layer. Identity verification at Companies House became a legal requirement on 18 November 2025, having been voluntary from 8 April 2025, and it covers directors, people with significant control and authorised corporate service providers.

Whether your practice acts as an ACSP or leaves verification to the client, the status of each director is one more thing a new company engagement has to track. That is covered further in the Companies House page.

Where the hours actually go #

Ask a practice how long onboarding takes and you get an estimate of the working time. Ask how long it takes from first conversation to first piece of chargeable work and the number is several times larger. The gap is where the cost hides, and it breaks down into three kinds of time.

Collecting the same information more than once

A new client typically supplies their details to a website form, again on an identity check, again on an engagement letter, and again when the practice sets them up internally. Nothing in that is judgement. It is the same facts, re-entered, with a fresh opportunity for a typo at each step.

Establishing state

"Where have we got to with the new client" is a question that gets reconstructed by hand, usually by opening an inbox. In a practice taking on a handful of clients a month, that reconstruction happens dozens of times per client across the onboarding period.

Dead waiting

A stalled authorisation or an unsigned letter costs nothing while somebody is watching it and a great deal when nobody is.

Which parts run on rules #

Runs on rules

  • Knowing which steps a given engagement requires (the list follows from the service)
  • Knowing which steps are done, open or stalled (if status is recorded somewhere single)
  • Prompting a client who has not signed or supplied (rules for the trigger)
  • Carrying the same facts across forms

Judgement

  • Deciding the risk rating of a client (yours to own)
  • Deciding whether an explanation is credible (with professional consequences)
  • Deciding whether to take the client at all

What this page is not saying #

  • That any part of customer due diligence can be delegated to software
  • That doing so would satisfy your obligations

The Money Laundering Regulations place the duty on the business, and your supervisor, whether HMRC or a professional body, will hold the practice to it. Anything that touches identity documents or client data also has to satisfy your UK GDPR duties, and the practice has to make that assessment itself.

What is defensible is that the tracking around those decisions, which is most of the elapsed time, is not a judgement problem at all. It is a list, a set of statuses and a set of dates. If you want a number for how much of your week that accounts for, the cost of admin time calculator is a starting point, and the free audit counts it properly.

Questions people ask

What has to happen before a practice can start work for a new client?
The exact list depends on the services and on whether you are supervised by a professional body or by HMRC, but it generally includes customer due diligence under the Money Laundering Regulations, a signed engagement letter, agent authorisation with HMRC, and professional clearance where there is an outgoing accountant. Each of those has its own waiting period, and they do not all run in parallel.
How long do onboarding records have to be kept?
HMRC guidance on the Money Laundering Regulations states that records must be kept for five years, beginning from the date a business relationship ends or the date a transaction is completed. That makes onboarding paperwork a retention obligation as well as a one off task.
Why does onboarding feel slower than it looks on paper?
Because most of the elapsed time is waiting, not working. Authorisation codes, client signatures, identity checks and clearance letters all sit in a queue owned by somebody outside the practice, and the practice usually discovers a step has stalled only when somebody thinks to look.
Which part of onboarding is most often the bottleneck?
Knowing the state of each new client at any moment. The individual steps are well understood. What is usually missing is a single current answer to "what is this one waiting on", which is why the same question gets asked in meetings week after week.

Where these numbers come from

  1. GOV.UK, Money Laundering Regulations: your responsibilities , read 19 September 2026
  2. GOV.UK, Money laundering supervision for accountancy service providers , read 19 September 2026
  3. GOV.UK, Who needs to register for money laundering supervision , read 19 September 2026
  4. GOV.UK, Verifying your identity for Companies House , read 19 September 2026

Last checked 19 September 2026.

Our workings are on the methodology page .

Free audit

A free audit for accountancy practices

One call, walking through a normal week. You get the tracker of every repeated job ranked by hours, a map of the top five, and the number of hours a month they could give back. Yours to keep either way.

Accountancy practices

Practice admin: onboarding, records chasing, deadlines and the January wall.

All of accountancy practices

Read next