Best Open Banking Platforms for Multi-Client Management in Accounting Firms [2025 Guide]

Handling data and bank feeds for multiple clients has long been a tedious part of accounting, chasing down PDFs, vetting spreadsheets, and wrangling statements from every bank. It’s inefficient, error-prone, and limits a firm’s ability to scale.

Fortuitously, Open Banking is transforming how multi-client management is done in accounting firms. A recent study found that firms can save up to 40 hours of work per employee per month by eliminating manual bank statement handling and switching to form-free data sharing through secure, automated tools

That means one employee can reclaim nearly half a working week every single month, time better spent on value-driven finance advisory and client services.

This isn’t just about convenience. It’s a productivity revolution. With more firms adopting Open Banking, accounting teams are empowered to focus on strategic growth and sophisticated reporting instead of admin desk work. In fact, a Mastercard‑Harris Poll revealed that 85% of businesses already use Open Banking, and 92% agree it’s essential for future‑proofing their operations, clearly framing it as a foundational shift, not just a nice-to-have.

By leveraging digital access to client bank data, firms unlock powerful efficiency gains: instant feeds instead of manual uploads, real-time financial data instead of delayed statements, and a single dashboard instead of scattered records. This is how financial data management for accountants should work and where multi-client management in accounting steps into the 21st century.

Why Multi-Client Management Needs Open Banking

For growing UK practices, multi-client management in accounting is no longer just about keeping records organised, it’s about maintaining compliance, accuracy, and efficiency across dozens of client portfolios. Without automation, managing 50–100 client accounts often means hours lost to:

• chasing statements,
• manual reconciliations, and
• re-keying data into accounting systems.

Open Banking as the Enabler

Open Banking changes this. By using a secure open banking API infrastructure, accountants can link directly to client accounts and receive verified transactions instantly.

This makes accounting client data management far smoother, removing the need for:

• back-and-forth emails,
• document uploads, and
• reliance on outdated spreadsheets.

Instead, firms gain access to live data feeds that refresh automatically.

Workflow Automation Benefits

The real benefit is in accounting workflow automation. Every client’s information balances, income streams, and transaction flows into one central system.

This shift allows accountants to:

• spend less time on admin,
• reduce repetitive manual work, and
• Focus more on delivering advice that matters.

Financial Data Management & Compliance

Equally important is financial data management for accountants. With Open Banking, data is standardised and audit-ready, which means:

• faster compliance checks,
• fewer errors, and
• smoother preparation for VAT returns, tax filings, or client reports.

The Bigger Picture

In short, Open Banking makes multi-client management in accounting scalable. It enables firms to handle a growing client base with the same resources, while still maintaining compliance and offering a better client experience.

Key Criteria for Choosing a Platform

Not every Open Banking provider is designed for accountants. When evaluating platforms for multi-client management in accounting, firms should look beyond payments and ensure the solution supports compliance, data accuracy, and automation.

1. FCA Authorisation & Compliance

The foundation of any platform is being an FCA-compliant Open Banking provider. This ensures client data is handled securely and meets the regulatory standards required for tax filings and audits.

2. Bank Coverage

For firms dealing with dozens of clients, wide bank connectivity is essential. Limited coverage leads to data gaps, which weakens both accounting client data management and compliance reporting.

3. Integration with Accounting Software

A provider should offer smooth connections to tools accountants already use, from Xero and QuickBooks to custom firm systems. This reduces manual uploads and supports accounting workflow automation across all client portfolios.

4. Deployment Speed & Onboarding Support

Firms need a solution that works quickly, without long implementation delays. A good open banking API for firms should be straightforward to integrate and come with strong support during onboarding.

5. Data Quality & Automation Features

Consistency in data is key. The best platforms standardise and categorise transactions, making financial data management for accountants more efficient and reliable. This ensures accurate reporting, faster reconciliations, and reduced admin overhead.

Finexer

Finexer is purpose-built for multi-client management in accounting, giving firms a single API that connects directly into client banking data while meeting strict FCA standards. Unlike global providers that divide resources across multiple regions, Finexer is focused entirely on the UK market, which makes it a strong fit for firms managing compliance-heavy workloads.

Best For

UK accounting firms that need fast, compliant access to client accounts and want to reduce the admin burden of manual processes.

Key Features

• FCA-authorised for both Account Information Services (AIS) and Payment Initiation Services (PIS).
• Usage-based pricing with no heavy upfront costs, making it affordable for firms of all sizes.
• White-label portals to offer clients a branded experience.
• Categorised transaction data that supports accounting client data management and audit readiness.
• 2–3x faster deployment than most market alternatives, with 3–5 weeks of onboarding support.

Why It Works for Accountants

Finexer makes accounting workflow simpler by feeding verified transactions, balances, and income streams directly into accounting systems. This reduces time spent on reconciliations and enables accountants to focus on higher-value tasks like tax planning and client advisory.

For firms struggling to scale, Finexer also supports financial data management for accountants at volume, giving practices confidence that client portfolios can grow without adding more admin overhead.

Modulr

Modulr is an FCA-regulated payments platform that provides API-driven infrastructure for businesses. While it is best known for powering B2B payments and payroll solutions, its services can also support accountants handling multiple client accounts.

For multi-client management in accounting, Modulr enables firms to access client accounts and manage disbursements more efficiently. Its APIs can be integrated into existing systems, which helps reduce manual work and improve overall accounting workflow automation.

In terms of financial data management for accountants, Modulr provides a stable setup for both incoming and outgoing payments, making it a useful option for firms that want to combine account access with payment capabilities. Though its primary focus is payments, accountants can still apply its infrastructure for client account management when required.

Bud

Bud is a UK-based data aggregation platform best known for its financial insights and enrichment tools. It provides an open banking API for firms that need to access transaction data and apply categorisation for analysis.

For accountants, Bud can support accounting client data management by improving how raw bank feeds are translated into categories, which may help in reporting and client reviews. It also offers features around personal finance insights, making it more relevant for firms that value enriched data.

However, when it comes to multi-client management in accounting, Bud’s strength lies more in data enrichment than workflow automation. It is best suited for firms with in-house systems that can make use of its categorisation features rather than those looking for a complete accounting-focused solution.

Plaid

Plaid is a well-known global open banking API for firms, offering connections to a wide range of banks and financial apps. Its focus has traditionally been on enabling fintech products, but the same infrastructure can also support accountants looking to centralise client data.

In the context of multi-client management in accounting, Plaid provides reliable access to client transactions and balances, which can help firms reduce manual data collection. Its developer-focused approach gives flexibility for practices that have in-house IT teams or prefer building custom integrations.

For accounting client data management, Plaid offers standardised transaction data that can be fed into reporting and reconciliation workflows. While not accounting-specific in design, it remains a widely used option for firms that want a broad, proven solution for accessing bank data.

Practical Example: Manual vs. Open Banking Workflows

Imagine an accounting firm with over 100 active clients.

Traditional Approach

• Staff request monthly bank statements from each client.
• Clients send PDFs or spreadsheets by email, often delayed.
• Accountants spend hours on data entry, cross-checking balances, and reconciling transactions.
• Compliance checks for tax or audit take even longer due to fragmented records.

This approach makes multi-client management in accounting time-consuming and prone to errors. It also slows down client service and leaves less capacity for growth.

Open Banking Approach

• Clients grant consent once through a secure open banking API for firms.
• Real-time transaction data flows directly into the firm’s accounting systems.
• Accounting client data management becomes centralised, with no manual uploads or repeated document chasing.
• With accounting workflow automation, reconciliations, VAT checks, and reports are generated with far less effort.
• Standardised feeds support financial data management for accountants, ensuring compliance records are complete and audit-ready.

By switching from manual to digital, firms can save hundreds of hours each year, free up staff for advisory work, and scale without increasing overhead.