Outsource Invoice Processing Services in London: Companies Guide (2026)
AC
Acumon Chartered Accountants·13 min read
Outsourced invoice processing can cover anything from basic invoice entry to a managed accounts payable function with approval workflows, supplier reconciliations, payment preparation, and reporting. This guide highlights a selection of London providers rather than ranking them, with a focus on companies that can take responsibility for recurring invoice and purchase ledger work.
Acumon
Acumon is a UK firm of chartered accountants and registered auditors providing outsourced invoice processing and wider accounting support to businesses in London and across the UK. The firm works with organisations ranging from growing owner-managed businesses and SMEs through to larger corporate groups that need additional support with day-to-day finance administration. Outsourced invoice processing can form part of a broader bookkeeping and accounts payable arrangement, helping businesses maintain accurate and up-to-date financial records.
Invoice processing typically involves receiving and recording supplier invoices, allocating transactions to the appropriate nominal codes and cost centres, checking supporting information, and managing invoices through established approval procedures. These activities can be integrated with purchase ledger management, supplier account reconciliation, and preparation of payment runs.
Acumon holds a Public Interest Entity (PIE) audit licence, allowing the firm to audit listed companies and other entities subject to enhanced regulatory oversight in the United Kingdom. PIE audits are subject to additional regulatory supervision and quality requirements, and only a limited number of firms are authorised to undertake this type of work.
In addition to its UK audit registration, Acumon also holds audit licences in several international financial centres, including the Cayman Islands, British Virgin Islands (BVI), Jersey, and Isle of Man. These licences enable the firm to support international corporate groups where entities are located across multiple jurisdictions.
Businesses with large transaction volumes or complex finance structures may require consistent processes across departments, entities, or reporting periods. A structured outsourced approach can help finance teams maintain visibility over outstanding invoices, creditor balances, approvals, and upcoming supplier payments.
Acumon works with finance teams and business owners to support outsourced invoice processing while helping organisations maintain reliable purchase ledger records, improve accounts payable workflows, and keep financial information organised as transaction volumes and operational requirements grow.
Outsourced Invoice Processing Service Capabilities
Acumon provides outsourced invoice processing services across a wide range of organisational structures and sectors.
These include:
UK limited companies and corporate groups
Public Interest Entities (PIEs) and regulated organisations
offshore holding companies and investment vehicles
Outsourced invoice processing engagements are typically led by senior professionals with direct involvement throughout the engagement.
Regulatory Licences and Registrations
Acumon holds several audit registrations that enable it to support organisations operating across multiple jurisdictions.
These include:
UK statutory audit registration
Public Interest Entity (PIE) audit licence
Jersey audit licence
Isle of Man audit licence
Cayman Islands audit licence
British Virgin Islands audit licence
These registrations allow the firm to provide audit services to groups that include entities in both the UK and key international financial centres.
Core Services
Acumon provides a range of services that support financial reporting and governance.
These include:
statutory external audit
group and subsidiary audits
Public Interest Entity (PIE) audits
charity and not-for-profit audit
audit of international group structures
internal audit and governance reviews
risk management and compliance support
Audit work is often delivered alongside discussions with management and boards regarding financial reporting processes and governance frameworks.
Many organisations initially encounter statutory audit requirements as they grow and exceed the audit exemption thresholds set out in the Companies Act.
Acumon works with businesses that are:
approaching their first statutory audit
preparing for external investment
expanding into international markets
operating within corporate group structures
Early engagement with an audit firm can help ensure that financial reporting systems and documentation are aligned with statutory audit requirements.
Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Saffery
Saffery offers purchase ledger management within its broader outsourcing practice. Its service is particularly relevant where businesses want supplier invoice administration connected with bookkeeping, cash flow monitoring, management accounts, and VAT work.
The purchase ledger team prepares regular creditor reports, identifies disputed items and available trade discounts, and organises proposed supplier payment runs at agreed intervals. Payments can then be raised through the client’s online banking arrangements for approval. Saffery also provides bookkeeping using systems including Sage and Xero, allowing purchase ledger activity to feed directly into wider accounting records.
Key Facts
Ideal for: Businesses requiring invoice processing within a broader outsourced accounting function
Address: 71 Queen Victoria Street, London EC4V 4BE, UK
Phone: +44 (0)20 7841 4000
Haggards Crowther
Haggards Crowther operates an outsourced accounting team from London and includes purchase ledger maintenance among its day-to-day finance services. The arrangement can extend from bookkeeping and invoice administration to management reporting, cash flow forecasting, payroll, and statutory accounting support.
Clients are allocated a dedicated client manager, with the firm’s published information stating that these managers are ACA, ACCA, or CIMA qualified and based in its London office. For companies wanting to outsource more than invoice entry alone, purchase ledger work can therefore sit within a wider finance function rather than being treated as an isolated administrative process.
Key Facts
Ideal for: Companies seeking ongoing outsourced finance support
Accace Adept UK provides accounting outsourcing from its London presence, with services covering digitisation of accounting documents, purchase invoice management, bookkeeping, and connected financial workflows.
Its model may be particularly relevant to companies looking to move away from manual invoice administration. Accace Adept describes an approach in which accounting documents and workflows can be digitised while purchase invoices are incorporated into the client’s accounting environment. The UK operation is part of a broader international BPO and advisory network, which may also be relevant to businesses with finance requirements spanning multiple jurisdictions.
Key Facts
Ideal for: Businesses digitising or outsourcing accounting workflows
Address: Berkeley Suite, 35 Berkeley Square, Mayfair, London W1J 5BF, United Kingdom
Phone: +44 20 7692 8481
Manage Your Accounts
Manage Your Accounts provides virtual finance services from London, including a dedicated purchase ledger function. Its published service scope covers invoice processing, management of invoice approvals, preparation of payment lists, and payment processing.
Businesses can combine these tasks with bookkeeping, sales ledger administration, VAT returns, payroll, cash flow management, management reporting, and virtual finance director support. This makes the service relevant where invoice processing is one component of a broader plan to externalise routine finance operations rather than a standalone data-entry requirement.
Key Facts
Ideal for: Businesses seeking a virtual finance team
Zapay focuses specifically on accounts payable outsourcing for UK businesses and operates from central London. Its workflow covers receiving and checking invoices, coordinating approvals and supplier communication, preparing payments, and reporting on the status of accounts payable work.
The company positions its service around documented processing steps and visibility over outstanding approvals and exceptions. It can work alongside common finance platforms including Xero, QuickBooks, Sage, Dynamics 365, and NetSuite, which gives businesses scope to outsource processing without necessarily replacing the accounting system already used internally.
Address: International House, 50 Essex Street, London, WC2R 3JF
Phone: 0203 951 4395
Coulman Scott Accountants
Coulman Scott Accountants provides bookkeeping support that includes processing purchase invoices and expenses as well as sales invoices, bank transactions, credit card transactions, and payroll journals.
Its bookkeeping packages can also cover purchase ledger reconciliations, supplier payment reports, accruals, prepayments, and financial reporting. The service therefore goes beyond simply transferring invoice information into accounting software. For businesses that need regular invoice processing together with reconciliation and reporting, these functions can be handled as part of the same bookkeeping arrangement.
Key Facts
Ideal for: Businesses requiring invoice processing and conventional bookkeeping
Cain & Co provides London bookkeeping services covering both sides of the invoicing cycle. Its published bookkeeping scope includes raising and posting sales invoices, coding and posting supplier invoices, allocating supplier payments to the purchase ledger, processing bank payments, and completing bank reconciliations.
The firm also handles journals, accruals, prepayments, and fixed asset records. This service profile may suit businesses whose main requirement is dependable transaction processing but which also want the resulting bookkeeping records maintained through the period rather than handed back immediately after invoices are entered.
Key Facts
Ideal for: Small businesses outsourcing transaction-level bookkeeping
P&K Associates provides bookkeeping services from locations in and around North London. Its purchase-side work includes purchase invoicing, checking purchase invoices, maintaining creditor listings, and purchase ledger administration.
The firm can also handle sales invoicing, debtor listings, allocations, debt collection, bank reconciliation, and VAT returns. Businesses can arrange bookkeeping at their own premises or through the firm’s offices, giving the service a more traditional outsourced accounting model than providers built entirely around remote processing.
Aztax Advisors provides outsourced bookkeeping and virtual finance support from Ilford, serving businesses in East London. Its day-to-day bookkeeping covers sales invoices, purchase invoices, receipts, expenses, and bank payments.
For companies outsourcing more of the back office, Aztax also describes purchase ledger management that includes receiving, checking, and processing supplier invoices. Expense claims, sales ledger administration, document management, and finance-related correspondence can also be included. The firm works with Xero, QuickBooks, Sage, and FreeAgent.
Key Facts
Ideal for: Small businesses and SMEs in East London
YMA Consultants offers bookkeeping services in London that cover the recording and management of sales and purchase invoices, bank transactions, accounts receivable, and accounts payable.
Supplier invoice processing can be combined with bank reconciliation, VAT record keeping, month-end procedures, management reporting, and customer payment follow-up. This broader scope may be useful for companies that initially want to outsource invoice processing but also need the bookkeeping records kept ready for VAT returns, year-end accounts, and management reporting.
Key Facts
Ideal for: Businesses combining invoice processing with regular bookkeeping
Core services: Supplier invoice processing, accounts payable, bank reconciliation, reporting
Specialization: Bookkeeping and accounting support
Location: London
Notable strength: Transaction processing connected with month-end bookkeeping
Address: 419 B North End Road, London, SW6 1NY, UK
Phone: +44 7502 373535
Wellden Turnbull
Wellden Turnbull provides outsourced accounting and bookkeeping services for businesses in London and Surrey. Purchase invoice processing is explicitly included in its bookkeeping offering alongside issuing and processing sales invoices.
The service can also incorporate bank reconciliation, VAT returns, payroll, and regular management accounts. Wellden Turnbull uses cloud accounting tools including Xero and Dext and can help clients set up Xero and train internal staff. This creates several possible delivery models, from outsourcing ongoing bookkeeping to establishing a cloud process that an internal team can subsequently operate.
Key Facts
Ideal for: Businesses outsourcing bookkeeping or moving invoice processes to cloud accounting
Address: 4th Floor, 49 St James’s Street, London, SW1A 1AH, UK
Phone: +44 (0)20 7381 2022
Milsted Langdon
Milsted Langdon provides outsourced finance functions through offices that include London. Purchase ledger management forms part of a broader service covering bookkeeping, cash flow management, management information, VAT, payroll, and finance director support.
Its outsourcing approach also incorporates finance technology. The firm describes systems that allow clients to scan, review, and approve invoices and payment runs remotely, which can be useful where management wants processing work outsourced while retaining visibility and approval authority. Hybrid arrangements are also available for businesses that already have an internal accounting team but need additional capacity.
Key Facts
Ideal for: Growing businesses outsourcing part or all of a finance function
Address: Work.Life, 7 St Cross St, London EC1N 8UB, UK
Phone: 0203 150 1113
BritTax
BritTax provides bookkeeping services from North London locations and bases its bookkeeping scope around transaction processing. Supplier invoices are included alongside customer invoices, bank transactions, and cash transactions.
The service also covers purchase ledger maintenance, recording supplier invoices and payments, supplier statement reconciliation, sales ledger maintenance, and bank reconciliation. This relatively conventional bookkeeping model may suit smaller businesses whose invoice outsourcing requirements centre on keeping supplier transactions accurately recorded and reconciled rather than implementing a separate enterprise accounts payable platform.
Key Facts
Ideal for: Small businesses outsourcing routine bookkeeping and supplier records
Address: Unit 53, Enfield Enterprise Centre, 26-28 Queensway, Enfield, EN3 4SA, UK
Phone: 020 3633 7344
Capita
Capita is a UK business process outsourcing company providing technology-enabled operational and finance services to public and private sector organisations. Its finance capabilities include accounts payable, accounts receivable, payment processing, invoice matching, and purchase order controls.
For outsourced invoice processing, Capita combines back-office process management with automation to handle high-volume finance operations. Its work with the London Borough of Bexley included automated accounts payable processes and improvements to invoice workflows and purchase order compliance.
Key Facts
Ideal for: Large organisations and public sector bodies
Specialization: Finance process outsourcing and automation
Location: London, UK
Contact Information
Website: www.capita.com
Facebook: www.facebook.com/Capitaplc
Twitter: x.com/CapitaPlc
LinkedIn: www.linkedin.com/company/capita
Instagram: www.instagram.com/lifeatcapita
Conclusion
London businesses have several ways to outsource invoice processing. Some providers focus closely on purchase ledgers and accounts payable, including invoice capture, approvals, supplier reconciliations, and payment preparation. Others treat invoice processing as one part of a broader outsourced bookkeeping or virtual finance function.
There is no single provider that fits every finance team. The practical choice depends on invoice volume, approval complexity, accounting software, the level of supplier interaction required, and whether the business wants to outsource only transaction processing or a larger part of its finance operation.
AC
Written by the Acumon team
Acumon is an ICAEW-registered firm of chartered accountants and registered auditors
based in London, with offices in Pitstone, Aylesbury and Bournemouth. Need advice on
anything covered here? Talk to us.
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