Most onboarding checklists circulating as templates are lists of tasks in the order somebody happened to think of them, which is why they get abandoned. A checklist that survives contact with a real client is organized by who has to act, because the practice's items and the client's items move at completely different speeds and blocking on the wrong one is the usual cause of a stalled onboarding.
What you need from them, gathered once
Identity and entity details, the documents your work requires, bank or billing details, and the names of everyone who will be involved and what each is allowed to do. The discipline is to ask once, completely, rather than in a sequence of remembered follow-ups over three weeks, because each additional request costs goodwill at exactly the moment a client is deciding whether they chose well. Batch the ask, and make what is outstanding visible so the client can work through it in their own time.
What they need from you, delivered without being chased
The engagement documentation, who their point of contact is, how to reach you and what the response expectation is, when the first substantive thing happens, and how they will see progress. These are cheap to provide and disproportionately shape the client's impression of the practice, because they are the only evidence a new client has that you are organized. A client who has to ask who their contact is has already learned something you did not want to teach.
Access, and the first review date
Two items get skipped and both cost later. Access means setting up the portal login, agreeing who on the client side sees what, and recording it, so that the question of who has access has an answer from day one rather than being reconstructed under pressure. The first review date means putting an actual date in the calendar for checking that the arrangement works. Onboardings without one do not conclude; they fade, and the practice never learns which parts of the run were wrong.
Questions people ask about customer onboarding checklist
How long should client onboarding take?
Practices commonly aim for two weeks, and the variable is almost always how fast the client returns what was asked. Batching the ask up front and making it visible does more for that number than anything on your own side.
Should the checklist be the same for every client?
The spine should be, with room for work-specific additions. Uniformity is what makes it possible to see that an onboarding has stalled; a bespoke run for every client cannot be compared to anything.
What is most often left off?
Recording who on the client side has access to what, and setting the first review date. Both are cheap at the start and expensive to reconstruct once the relationship is under way.