Bookkeeping client onboarding checklist: the first 30 days with a new client

The first 30 days with a new client decide how the next three years go. Clients form their habits early: how they send documents, how quickly they answer queries, what they think is included in the fee. A bookkeeper who onboards by saying “send me what you have” gets a shoebox and an open-ended scope. One who onboards with a checklist gets access on day one, a known starting position, and a client who understands the routine. This guide is that checklist, in five stages, with the tax authority access steps for the UK, Australia, New Zealand, Canada, and Singapore. Regulatory and software facts are linked in the Sources section.

The five stages

Stage 1: qualify and scope

Ask for read-only access to the existing ledger, or the last set of accounts and three months of bank statements, before quoting. You are looking for five numbers and one judgement:

• Bank and card accounts, and transactions per month on each.
• Supplier bills and sales invoices per month.
• Employees on payroll, and who runs it.
• Tax registrations and how often each return is filed.
• The date the books were last reconciled.
• The judgement: will this client send documents and answer questions?

The fifth number decides whether this is ordinary onboarding or a rescue. If the books are more than a few months behind, scope and price the backlog as its own project; see catch-up bookkeeping. How to turn the other numbers into a fee is covered in pricing bookkeeping services.

Stage 2: engage

The engagement letter

Put the arrangement in writing before any work starts. A letter that prevents arguments covers:

• Services in scope, as a list, with frequency: weekly bank reconciliation, monthly close by a named working day, quarterly VAT or GST return.
• Services out of scope, also as a list: year-end accounts, income tax returns, payroll, backlog work, software training.
• What the client must do: send documents through the agreed channel, answer queries within an agreed number of days, approve returns before filing.
• What happens when they do not: late documents go into the following period; extra work is quoted separately.
• Fees, when they are reviewed, and how they are collected.
• Who owns what: the client owns the ledger subscription and data; you hold working papers.
• How either side ends it, and what you hand over.

Your professional body will have a template that reflects local requirements. Use it as the base.

Identity and regulatory checks

Whether you must verify a new client’s identity depends on where you practise.

In the UK the answer is yes. HMRC’s guidance lists professional bookkeeping services among accountancy services, and an accountancy service provider must register with HMRC for anti-money laundering supervision unless a professional body already supervises it ^[1] . Supervised businesses must carry out customer due diligence when establishing a business relationship: identify the customer, check they are who they say they are, and identify any beneficial owner. The records must be kept for 5 years from the date the relationship ends ^[2] .

In Australia the check runs the other way first: you must be registered with the Tax Practitioners Board to provide BAS services for a fee or other reward ^[3] . Confirm your own registration covers the services you are about to sell.

Elsewhere, check what your professional body and local law require before relying on this guide.

Stage 3: access

Ask for your own user everywhere. Shared logins break the audit trail and usually breach the software’s terms.

The ledger

• Xero. A user with the edit users permission goes to Settings, then Users, then New user, enters your details, picks a role, and sends the invite. Adding users, including an accountant or bookkeeper, is free of charge, and the invite expires after 14 days ^[4] .
• QuickBooks Online. A primary or company admin goes to Settings, then Manage users, opens the Accounting Firms tab, and selects Invite firm. Accountant users invited this way do not count toward the client’s user limit ^[5] .

The tax authority

This is the step that most often stalls, because in several countries only the client can start it. Send instructions on day one.

Two details from the ATO’s agent checklist are worth building into your instructions. You cannot ask the client to share their myID or a login code so that you can complete the nomination for them. And link only at the account level you are engaged for: linking at an account that already has an agent removes that agent, which can leave another practitioner unable to lodge ^[11] .

Everything else

• Bank and card accounts: working feeds into the ledger, plus read access or monthly statements.
• Payroll software, if in scope.
• Supplier portals that issue bills without emailing them (utilities, telecoms, fuel cards).
• Sales platforms and payment processors, for payout reports.
• The previous bookkeeper or accountant: closing trial balance, fixed asset register, and anything open with the tax authority.

Stage 4: baseline

Before you post anything, record where the books stand. This protects you: problems that existed before you arrived are documented as such.

If the client is moving to a new ledger. In Xero, opening balances are entered as conversion balances. You need the old system’s trial balance for the day before the conversion date. Balances can be keyed one by one, imported with the chart of accounts, or handled by a conversion specialist. Xero lets you begin with just the bank balance, but reports and bank balances are not accurate until the rest are entered ^[12] .

If you are taking over an existing ledger, check and write down:

• The last date each bank and card account was reconciled, and whether the reconciled balance agrees to the statement.
• The lock date or closing date, if any.
• Balances in suspense, clearing, and undeposited funds accounts.
• Receivables and payables older than 90 days.
• The VAT or GST control account against the last filed return.
• Returns filed, returns overdue, and any payment arrangements.
• The chart of accounts: duplicates, unused accounts, and catch-all codes.

Send the client a one-page summary: what is fine, what needs fixing, and whether the fixing is inside the fee.

Stage 5: the first month

The first month sets the routine, so run it the way you intend to continue.

• One channel for documents. Pick it, show the client how to use it, and decline documents sent any other way. See how to stop chasing client receipts.
• One channel for queries, with a single weekly list instead of a message per question.
• A fixed calendar. Tell the client the dates: documents by the 3rd working day, queries answered by the 5th, figures on the 8th.
• Run a full close, even if the first month is light. The sequence is in the month-end close process.
• Review at day 30. A 20-minute call: what worked, what was late, what changes next month.

Red flags to act on early

• No response to the access requests within a week.
• Documents arriving through three different routes.
• Personal spending through the business account with no explanation.
• A previous bookkeeper who left abruptly and will not hand over.
• Pressure to file a return before the figures are checked.

None of these ends an engagement by default. Each needs a conversation in month one, not month six.

Where ExpenseFlow fits

ExpenseFlow covers the document channel in Stage 5. A firm adds each client as its own file, connects that file to the client’s Xero or QuickBooks Online ledger, and assigns the team members who will work on it. The client gets a dedicated email address to forward bills and receipts to, and can also upload files or pick them from Google Drive. Documents are read line by line, coded against that client’s chart of accounts, and held in a review queue until someone approves them; corrections you make are learned per client and applied to the same supplier next time.

Billing is per client file with unlimited staff seats, so a new client does not mean buying seats for the team; see pricing for bookkeepers. ExpenseFlow does not carry out identity checks, draft engagement letters, or handle tax authority authorisations.