Company lists · Data refreshed August 2026

Top 25 Accounting outsourcing companies based in the United Kingdom

Name: Accounting outsourcing companies based in the United Kingdom
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Aug 30, 2026 1,949 companies tracked

There are 1,949 accounting outsourcing companies headquartered in the United Kingdom (RevenueBase, August 2026). RevenueBase tracks 12,309 professional contacts across them, including 2,568 with verified work emails and 397 with mobile numbers. London is the largest hub.

This list covers accounting outsourcing companies headquartered in the United Kingdom, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, how directly it supports the match, and when it was last checked. Data refreshed August 30, 2026.

1,949Companies

12,309Contacts tracked

2,568Verified emails

397Mobile numbers

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The 25 largest accounting outsourcing companies based in the United Kingdom

Ranked by team size

Top 25 of 1,949 accounting outsourcing companies based in the United Kingdom, ranked by team size, largest first. Data refreshed Aug 30, 2026. Evidence rates how directly each company's own description names accounting outsourcing companies: strong (names it), partial (names part of it), indirect (matched on its full profile rather than the summary shown). Click a count to unlock that company's people.
#	Company	Headquarters	Employees	Contacts	Verified emails
1	OutbooksStrong evidence “Outbooks is a leading provider of outsourcing services to accounting and bookkeeping firms.” Source: company website · checked Aug 30, 2026	London, United Kingdom	201-500	475	39
2	SKS Business ServicesIndirect evidence “At SKS, we pride ourselves on being different.” Source: company website · checked Aug 30, 2026	London, United Kingdom	501-1,000	321	217
3	GI OutsourcingPartial evidence “GI Outsourcing is a UK-based accountants outsourcing firm.” Source: company website · checked Aug 30, 2026	London, United Kingdom	201-500	317	168
4	Obox Solution LTDPartial evidence “At Obox Solution Ltd, we support accounting firms and mid-market businesses by providing tailored virtual staffing solutions for bookkeeping, payroll, CFO services, tax, financial…” Source: company website · checked Aug 30, 2026	London, United Kingdom	201-500	132	12
5	Intelligent OutsourcingStrong evidence “Intelligent Outsourcing (iO) is an offshoring company in the Philippines dedicated to supporting UK accounting practices.” Source: company website · checked Aug 30, 2026	Tunbridge Wells, United Kingdom	51-200	119	56
6	Initor Global UKIndirect evidence “As attention turns to the new fiscal year, accountants across the UK are finalising plans to boost growth and productivity and improve profitability.” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	108	43
7	DebitamPartial evidence “Online Accounting Service \| Bookkeeping \| Payroll \| Personal Tax Return Filing to HMRC \| Corporation Tax Filing \| HMRC ONLINE FILING: Our aim is to help small business owners` tax…” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	103	30
8	SJD AccountancyIndirect evidence “SJD is now Caroola Accountancy!” Source: company website · checked Aug 30, 2026	Hemel Hempstead, United Kingdom	501-1,000	102	2
9	Paperchase Business Services LTDIndirect evidence “Paperchase Business Services Ltd (PBSL) is a firm of accountants, taxation and business advisors based in South London.” Source: company website · checked Aug 30, 2026	London Croydon, United Kingdom	501-1,000	100	18
10	Affinity Outsourcing LimitedStrong evidence “Affinity Outsourcing is an accountancy outsourcing company that specialises in outsourcing for Accounting Practices.” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	96	32
11	Sapphire Info Solutions P LTDStrong evidence “Sapphire is an accounting outsourcing company set up for accounting firms in UK and is based in India.” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	88	28
12	Base Practice Support LTD Baseline Practice Support Smc-Pvt LTDIndirect evidence “Base Practice Support Ltd is the UK's fastest-growing Accountancy Practice Support company.” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	75	19
13	Affinity Associates LimitedPartial evidence “Affinity Associates Limited is a leading accounting firm based in Wembley, London, UK, and is regulated and authorised for public practice by both the ICAEW (Institute of…” Source: company website · checked Aug 30, 2026	Wembley, United Kingdom	201-500	64	30
14	The Accountancy PartnershipPartial evidence “We offer online accounting services which simplify tax and finances for small businesses, by providing a fresh alternative to old-school high street accountants.” Source: company website · checked Aug 30, 2026	Wirral, United Kingdom	51-200	63	33
15	StellaripeIndirect evidence “We are on a mission to help accountants to grow their accountancy practice and become more profitable.” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	57	40
16	Acenteus AccountingPartial evidence “Acenteus Accounting, legally known as Acenteus CCA Global Ltd is a UK-registered outsourced accounting and finance partner delivering secure, cloud-enabled support for…” Source: company website · checked Aug 30, 2026	United Kingdom	51-200	54	3
17	Green & PurpleIndirect evidence “We offer a CFO-led virtual finance team.” Source: company website · checked Aug 30, 2026	Cambridge, United Kingdom	51-200	44	32
18	Accountsbytes Private LimitedIndirect evidence “AccountsBytes believes in INTACT a.” Source: company website · checked Aug 30, 2026	Rugby, United Kingdom	51-200	43	3
19	AscendantPartial evidence “Accounting.” Source: company website · checked Aug 30, 2026	London, United Kingdom	201-500	39	26
20	Bookcheck LTDIndirect evidence “Our clients rely on us to remove book-keeping hassle and improve their profitability by using our top quality financial reports based on professionally reconciled book-keeping.” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	29	24
21	Finex AccountingStrong evidence “Finex Accounting is an outsourcing accountancy service provider.” Source: company website · checked Aug 30, 2026	Manchester, United Kingdom	51-200	27	8
22	Doshi OutsourcingIndirect evidence “In 1995 the Doshi family set up Doshi & Co in London as an accountancy practice for UK clients and simply offshored their very own back office in Gujarat, India in - a location…” Source: company website · checked Aug 30, 2026	Croydon, United Kingdom	201-500	20	1
23	AAT Management ConsultantsIndirect evidence “WHY AAT?” Source: company website · checked Aug 30, 2026	London, United Kingdom	51-200	15	1
24	The Financial Management CentreIndirect evidence “The Financial Management Centre is a leading financial management consultancy that is committed to helping organisations achieve performance excellence.” Source: company website · checked Aug 30, 2026	Crawley, United Kingdom	51-200	15	1
25	Clearcut Outsourcing UKPartial evidence “Our mission at Clearcut Outsourcing is to provide exceptional accountancy outsourcing services to accountancy firms of all sizes.” Source: company website · checked Aug 30, 2026	Manchester, United Kingdom	201-500	13	1

Showing 25 of 1,949 accounting outsourcing companies based in the United Kingdom

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Accounting outsourcing companies based in the United Kingdom at a glance

As of Aug 30, 2026

1-10Median size (employees)

LondonLargest hub · 366 HQs

397Contacts with mobile numbers

Aug 30, 2026Data refreshed

Companies by employee count

1-10

1,530

11-50

276

51-200

201-500

501-1,000

1,001-5,000

Accounting outsourcing companies by metro

Metro	Companies
Accounting outsourcing companies in London	366
Accounting outsourcing companies in Manchester	36
Accounting outsourcing companies in Bristol	27
Accounting outsourcing companies in Birmingham	26
Accounting outsourcing companies in Glasgow	19
Accounting outsourcing companies in Leicester	18
Accounting outsourcing companies in Nottingham	16

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among accounting outsourcing companies, so some rows will be adjacent to the category rather than pure plays. The description and evidence rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 21.3 million companies and 398.9 million professional contacts resolved from primary sources.
What qualifies: Companies headquartered in the United Kingdom whose own description of what they do matches “accounting outsourcing companies”. Matching reads each company's description, not its industry code or its name.
What we exclude: Companies whose own description does not clearly place them among accounting outsourcing companies, and records with no verified work email. Companies headquartered outside United Kingdom are excluded even when they keep an office there.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and an evidence rating so you can judge each match yourself.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every listed company carries at least one verified work email, 2,568 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on August 30, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

How many accounting outsourcing companies are there based in the United Kingdom?

There are 1,949 accounting outsourcing companies headquartered in the United Kingdom as of August 2026 (RevenueBase).

What is the largest company on this list?

Outbooks, headquartered in London, tops this list with the largest team on record.

Which city has the most accounting outsourcing companies?

London leads with 366 headquartered companies, followed by Manchester (36) and Bristol (27).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 2,568 verified decision-maker contacts tracked across these 1,949 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on August 30, 2026.

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About this data

RevenueBase is a B2B contact data platform. Its company graph covers 21.3 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph, the same data that powers RevenueBase's B2B data products and the free research portal.