How to Build a Client Onboarding Portal for an Accounting Firm on Bubble.io
New client onboarding is one of the most time-consuming non-billable activities in an accounting firm. Collecting engagement letters, AML/KYC documents, prior year accounts, and setup information via email takes 2-4 weeks and generates 15-20 emails per client. A structured Bubble.io onboarding portal completes the same process in 3-5 days with minimal accountant involvement.
The Business Case
Client onboarding is the first impression a new client has of the firm’s operational quality. An onboarding process that requires the client to receive and respond to 8-10 individual emails, upload documents to consumer file-sharing services, and chase the firm for confirmation that everything has been received signals disorganisation and sets a poor expectation for the rest of the engagement. A structured onboarding portal that guides the client through a clear, step-by-step process, stores everything securely, and confirms completion automatically signals competence and professionalism. SA’s accounting firm clients consistently report that clients comment positively on the onboarding portal in the first engagement meeting — a word-of-mouth referral opportunity that the email-based onboarding process does not create.
The Six Steps
Step 1: Engagement letter delivery and acknowledgement
The engagement letter (the formal document that defines the services to be provided, the fee basis, and the terms of the engagement) is delivered to the client through the portal for electronic acknowledgement. The client reads the letter in the portal and clicks Acknowledge and Accept; the portal records the timestamp and the client’s name as the acknowledgement record. For firms that require a handwritten signature, the engagement letter is delivered via an integrated e-signature workflow (DocuSign or Adobe Sign via the API Connector).
Step 2: Anti-money laundering (AML) identity verification
The portal presents the AML/KYC document collection form: clients are prompted to upload photographic identification (passport or driving licence) and proof of address (utility bill or bank statement dated within 3 months). The portal checks that both documents have been uploaded before allowing the client to proceed to step 3. The documents are stored in the Bubble.io database with access restricted to authorised firm staff only; they are never sent via email.
Step 3: Business and personal information collection
A structured form collects the information the accountant needs to set up the client record: company name, registered number, UTR number, VAT registration number (if applicable), director/shareholder details, accounting year end, payroll information (if applicable), and any specific circumstances relevant to the engagement. This form replaces the email questionnaire that most firms send and that clients typically return incompletely, requiring multiple follow-up emails.
Step 4: Prior accountant information and authority letter
If the client is transferring from a previous accountant, the portal collects the prior accountant’s contact details and presents an authority letter for the client to sign (via the e-signature integration), authorising the previous accountant to release the client’s records to the new firm. The signed authority letter is stored in the portal and the accountant is notified to send it to the previous accountant.
Step 5: Prior year documents
The portal requests the client to upload their prior year documents: the previous year’s accounts (if filed by the previous accountant), the prior year tax return (if relevant), and any other documents the accountant has identified as needed for the first year’s engagement. Automated reminders are sent every 3 days until all required documents are uploaded.
Step 6: Onboarding completion and handover to the fee earner
When all required steps are completed, the portal sends a completion notification to the client (confirming that the onboarding is complete and what happens next) and a handover notification to the responsible fee earner (with a summary of the information collected and links to the uploaded documents). The client record is automatically created or updated in the accounting software via the API integration, and the first workflow item (the first deliverable for the new client) is created in the practice management system.
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Q: Does the onboarding portal need to comply with the ICAEW or ACCA AML requirements?
Yes. The portal’s AML/KYC document collection functionality must support the firm’s compliance with the Money Laundering Regulations 2017 (UK) or equivalent legislation in other jurisdictions. The key requirements: the portal must collect and store the prescribed identification documents (photographic ID and proof of address); the documents must be accessible to the firm’s Money Laundering Reporting Officer (MLRO) for review; the portal must record when the documents were collected and when they were reviewed; and the documents must be retained for the prescribed period (5 years after the end of the business relationship in the UK). SA builds these compliance workflows into every accounting firm onboarding portal build.
Q: Can the onboarding portal integrate with my existing accounting software (Xero, QuickBooks, IRIS, Sage)?
Yes. Each of these platforms exposes a REST API that Bubble.io’s API Connector can call. The most common integration: after the client completes the onboarding portal, the portal creates a new client record in the accounting software using the information collected during onboarding (company name, UTR, VAT number, director details), eliminating the manual data entry step that currently follows client onboarding. SA configures this integration as part of every accounting firm onboarding portal build.
Q: How do I handle clients who are not comfortable using an online portal?
For clients who prefer paper or telephone-based onboarding (typically older clients or less technology-confident individuals), the portal includes an alternative: a printable version of the information collection form, a postal address for document submission, and a note that clients can call the firm to complete the process by telephone. The portal tracks these clients as ‘assisted onboarding’ and assigns a team member to manage the process manually. SA builds the manual onboarding fallback into every accounting firm portal as a standard feature.
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