Company lists · Data refreshed September 2026

Top 25 Outsourced administration services based in the United Kingdom

Name: Outsourced administration services based in the United Kingdom
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 21, 2026 540 companies tracked

RevenueBase identified 540 outsourced administration services headquartered in the United Kingdom as of September 2026 and tracks 2,202 professional contacts across them, including 652 with verified work emails. London is the largest hub.

This list covers outsourced administration services 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, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 21, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 21, 2026 86% judged on-target in blind review

540Companies

2,202Contacts tracked

652Verified emails

Explore this list → Free signup · no credit card · 500 free credits

The 25 largest outsourced administration services based in the United Kingdom

Ranked by team size

Top 25 of 540 outsourced administration services based in the United Kingdom, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to outsourced administration services: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	GI Outsourcing	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	201-500	311 contacts →
	Partial evidence “GI Outsourcing is a UK-based accountants outsourcing firm.” Source: RevenueBase Database · checked Sep 21, 2026
2	Strictly Education LTD	Partial evidence	Milton Keynes, United KingdomHQ checked Sep 21, 2026	51-200	111 contacts →
	Partial evidence “Strictly Education exists to make the management and administration of educational establishments easier and less stressful.” Source: RevenueBase Database · checked Sep 21, 2026
3	SOLVD	Indirect evidence	Glasgow, United KingdomHQ checked Sep 21, 2026	51-200	74 contacts →
	Indirect evidence “Streamline your business with our bespoke support services.” Source: RevenueBase Database · checked Sep 21, 2026
4	Industry Resource Services IRS Group	Indirect evidence	Beccles, United KingdomHQ checked Sep 21, 2026	11-50	47 contacts →
	Indirect evidence “Leading providers of specialist support services.” Source: RevenueBase Database · checked Sep 21, 2026
5	Uris Group	Partial evidence	Doncaster, United KingdomHQ checked Sep 21, 2026	51-200	42 contacts →
	Partial evidence “There has always been a demand in the insurance market for third party administration services to allow insurers, brokers, corporates and affinities to focus on their core…” Source: RevenueBase Database · checked Sep 21, 2026
6	Factotum	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	51-200	41 contacts →
	Indirect evidence “Welcome to Factotum-your secret weapon for streamlined business success!” Source: RevenueBase Database · checked Sep 21, 2026
7	Go-To Outsourcing	Partial evidence	Bromsgrove, United KingdomHQ checked Sep 21, 2026	11-50	32 contacts →
	Partial evidence “Almost every business can save time and money with smart outsourcing from Go-To - how much depends on you.” Source: RevenueBase Database · checked Sep 21, 2026
8	Freedom Outsourcing	Partial evidence	Sutton Coldfield, United KingdomHQ checked Sep 21, 2026	11-50	25 contacts →
	Partial evidence “At Freedom Outsourcing, we specialise in Business Process Outsourcing (BPO) to help businesses save money and grow faster with UK managed outsourcing solutions.” Source: RevenueBase Database · checked Sep 21, 2026
9	Wessex Group	Partial evidence	Winchester, United KingdomHQ checked Sep 21, 2026	51-200	24 contacts →
	Partial evidence “Wessex Group is an independent provider of intermediary services to the financial services industry specialising in the administration of personal lines insurance.” Source: RevenueBase Database · checked Sep 21, 2026
10	Oakford Advisors LTD	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	24 contacts →
	Partial evidence “Oakford Advisors Ltd, a Centralis Group company, is an outsourced business services firm which specialises in providing back-office support to start-up or existing companies…” Source: RevenueBase Database · checked Sep 21, 2026
11	Backoffice Nationwide LTD	Indirect evidence	Selby, United KingdomHQ checked Sep 21, 2026	11-50	15 contacts →
	Indirect evidence “Here at Backoffice we offer a choice of services designed to meet both the agency and operative’s needs.” Source: RevenueBase Database · checked Sep 21, 2026
12	Withall & CO LTD	Partial evidence	West Wickham, United KingdomHQ checked Sep 21, 2026	11-50	15 contacts →
	Partial evidence “When you engage us to act as your outsourced finance team, we not only provide financial and business support, but in conjunction with our wider community of legal experts and tax…” Source: RevenueBase Database · checked Sep 21, 2026
13	Hour Hands LTD	Indirect evidence	Harpenden, United KingdomHQ checked Sep 21, 2026	1-10	15 contacts →
	Indirect evidence “Bookkeeping, business support and PA services.” Source: RevenueBase Database · checked Sep 21, 2026
14	Intuitive Support	Strong evidence	Colchester, United KingdomHQ checked Sep 21, 2026	11-50	14 contacts →
	Strong evidence “The Intuitive Team has been providing outsourced administration support to UK financial advice firms since 2014.” Source: RevenueBase Database · checked Sep 21, 2026
15	Modina	Partial evidence	Hitchin, United KingdomHQ checked Sep 21, 2026	1-10	14 contacts →
	Partial evidence “Modina is a friendly, professional outsourcing service dedicated to helping you stay in control of your bookkeeping and payroll.” Source: RevenueBase Database · checked Sep 21, 2026
16	Adviser Outsourcing LTD	Partial evidence	Hinckley, United KingdomHQ checked Sep 21, 2026	1-10	13 contacts →
	Partial evidence “Adviser Outsourcing provide bespoke outsourced and consultancy services to Financial advice firms that provide reliability, flexibility and above all else expertise within the…” Source: RevenueBase Database · checked Sep 21, 2026
17	BCA Accountants And Business Advisors	Indirect evidence	Hull, United KingdomHQ checked Sep 21, 2026	11-50	12 contacts →
	Indirect evidence “From the decision to start up, the development of strategic options and planning, the implementation of control & performance measurement systems, and profit distribution each…” Source: RevenueBase Database · checked Sep 21, 2026
18	MNE Accounting	Partial evidence	Leicester, United KingdomHQ checked Sep 21, 2026	11-50	12 contacts →
	Partial evidence “MNE is an innovative firm in the accountancy industry offering a full accounts outsourcing service for some of the UK’s leading businesses and brands.” Source: RevenueBase Database · checked Sep 21, 2026
19	IH Solutions	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	12 contacts →
	Indirect evidence “We bring our extensive industry experience to the hum-drum of finance, HR, operations, marketing and compliance so that you can focus on delivering the fun to your customers.” Source: RevenueBase Database · checked Sep 21, 2026
20	The Paperwork Team	Indirect evidence	Shipston-on-stour, United KingdomHQ checked Sep 21, 2026	11-50	10 contacts →
	Indirect evidence “Bookkeeping, Admin and PA support.” Source: RevenueBase Database · checked Sep 21, 2026
21	Admin Business Solutions	Strong evidence	Solihull, United KingdomHQ checked Sep 21, 2026	11-50	10 contacts →
	Strong evidence “Admin Business Solutions Limited (ABS) was founded in 1998, with the key objective to offer a dedicated and comprehensive means of outsource support for Fleet Administration…” Source: RevenueBase Database · checked Sep 21, 2026
22	Hive HR Solutions LTD	Indirect evidence	Horsham, United KingdomHQ checked Sep 21, 2026	1-10	9 contacts →
	Indirect evidence “We provide businesses with a robust, reliable, and helpful HR service, that offers complete peace of mind.” Source: RevenueBase Database · checked Sep 21, 2026
23	Efficiency Back Office Services PTY LTD	Strong evidence	Crawley, United KingdomHQ checked Sep 21, 2026	11-50	8 contacts →
	Strong evidence “Efficiency Back Office Services (Pty) Ltd started in 2022 and is an outsourcing back-office administration company that specialises in providing skilled and fully managed…” Source: RevenueBase Database · checked Sep 21, 2026
24	Zion Accountants & Consultants	Partial evidence	Croydon, United KingdomHQ checked Sep 21, 2026	1-10	8 contacts →
	Partial evidence “We are a team of professionals to assist in the start-up, planning, and administration of the business in order to meet the accounting and tax requirements of individuals, small…” Source: RevenueBase Database · checked Sep 21, 2026
25	Accuco	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	7 contacts →
	Partial evidence “Providing "evolved administration" in a forward-thinking way.” Source: RevenueBase Database · checked Sep 21, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: outsourced administration services. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names outsourced administration services.
Partial evidence: Its own public description names part of outsourced administration services, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name outsourced administration services. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 540 outsourced administration services based in the United Kingdom

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 652 reachable decision-makers.

Free signup · no credit card

View the full list →

Outsourced administration services based in the United Kingdom at a glance

As of Sep 21, 2026

29.6%Verified-email coverage

4.1Average contacts per company

1-10Median size (employees)

16.1%Largest-city concentration · London

Sep 21, 2026Page data refreshed

Companies by employee count

1-10

454

11-50

51-200

201-500

1,001-5,000

Email recency for this list is measured worldwide rather than for United Kingdom, so it is reported there. Company counts and contact totals on this page are exact for United Kingdom, over 540 companies.

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 outsourced administration services, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in the United Kingdom whose own description of what they do matches “outsourced administration services”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names outsourced administration services), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among outsourced administration services, 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 its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
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, 652 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 September 21, 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.

Outsourced administration services by metro

Outsourced administration services in London87

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names outsourced administration services, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many outsourced administration services are there based in the United Kingdom?

RevenueBase identified 540 outsourced administration services headquartered in the United Kingdom as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

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

Which city has the most outsourced administration services?

London leads with 87 headquartered companies, followed by Manchester (15) and Glasgow (10).

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 652 verified decision-maker contacts tracked across these 540 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 21, 2026.

Ready to reach these companies? Verified emails and direct dials for all 540 outsourced administration services based in the United Kingdom. Start with a free account, no credit card.

Download this list →

Related lists

Outsourced administration services by geography

Browse the directory

About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 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 with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.