Company lists · Data refreshed September 2026

Top 25 HR systems based in London, United Kingdom

Name: HR systems based in London, United Kingdom
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 21, 2026 451 companies tracked

RevenueBase identified 451 HR systems headquartered in London, United Kingdom as of September 2026 and tracks 6,259 professional contacts across them, including 1,049 with verified work emails. London is the largest hub.

This list covers HR systems headquartered in London, 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

451Companies

6,259Contacts tracked

1,049Verified emails

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The 25 largest HR systems based in London, United Kingdom

Ranked by team size

Top 25 of 451 HR systems based in London, United Kingdom, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to HR systems: 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	NGA Human Resources, An Alight Company	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	1,001-5,000	2,734 contacts →
	Partial evidence “At Alight \| NGA Human Resources our mission is to make HR work better.” Source: RevenueBase Database · checked Sep 21, 2026
2	Huntress	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	51-200	289 contacts →
	Indirect evidence “Since our establishment in Huntress has been at the forefront of recruitment across a range of specialist sectors.” Source: RevenueBase Database · checked Sep 21, 2026
3	PLUMM	Strong evidence	London, United KingdomHQ checked Sep 21, 2026	n/a	155 contacts →
	Strong evidence “Plumm is the next-generation HR platform designed to replace your patchwork of tools with one powerful, integrated system.” Source: RevenueBase Database · checked Sep 21, 2026
4	Oakleaf Partnership	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	51-200	57 contacts →
	Partial evidence “Since 2005, Oakleaf Partnership has been successfully placing people into jobs across every HR discipline, in every sector imaginable.” Source: RevenueBase Database · checked Sep 21, 2026
5	Hunter Adams	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	51-200	53 contacts →
	Partial evidence “Hunter Adams is an employee-owned HR consultancy, Interim and recruitment business.” Source: RevenueBase Database · checked Sep 21, 2026
6	HR Grapevine	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	49 contacts →
	Partial evidence “HR Grapevine is the leading digital resource for HR professionals.” Source: RevenueBase Database · checked Sep 21, 2026
7	Project Recruit	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	45 contacts →
	Indirect evidence “At Project Recruit, getting to know our clients is at the heart of what we do.” Source: RevenueBase Database · checked Sep 21, 2026
8	Fitzgerald	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	38 contacts →
	Partial evidence “We’re the full-service HR consultancy that synchronises seamlessly with your business.” Source: RevenueBase Database · checked Sep 21, 2026
9	Whitecollars	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	35 contacts →
	Partial evidence “We are Whitecollars, the global Human Resource consulting and recruitment agency that supports your business growth with affordable, flat-fee recruitment solutions and tailored HR…” Source: RevenueBase Database · checked Sep 21, 2026
10	The Opra Group	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	34 contacts →
	Indirect evidence “The OPRA Group provides a complete portfolio of People Solutions designed to help organisations make confident, consistent, and future‑focused decisions.” Source: RevenueBase Database · checked Sep 21, 2026
11	UDDER	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	30 contacts →
	Partial evidence “We help forward-thinking HR, TA and Learning leaders to take full advantage of the ROI that modern HR tech can bring to their organisations.” Source: RevenueBase Database · checked Sep 21, 2026
12	Verto HR	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	201-500	30 contacts →
	Partial evidence “Verto HR, professional in-house HR experts, jointly managing your external on-site property staff.” Source: RevenueBase Database · checked Sep 21, 2026
13	Journeyhr	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	28 contacts →
	Indirect evidence “Welcome to JourneyHR.” Source: RevenueBase Database · checked Sep 21, 2026
14	Offerletter HR Services	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	28 contacts →
	Partial evidence “Offer Letter, is a focused Talent Search and HR Consulting Services Company, which is rapidly emerging by delivering high quality service to its clients from IT and other sectors.” Source: RevenueBase Database · checked Sep 21, 2026
15	AJ FLX	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	27 contacts →
	Indirect evidence “AJ FLX is the embedded Talent and People solution for venture-backed startups and scaleups.” Source: RevenueBase Database · checked Sep 21, 2026
16	Strategic Dimensions	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	23 contacts →
	Partial evidence “Strategic Dimensions is an executive search business set up in 1994 to recruit senior HR professionals across a range of sectors.” Source: RevenueBase Database · checked Sep 21, 2026
17	People 1st	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	23 contacts →
	Partial evidence “With over 80 years combined experience running global HR events, the team at People 1st \| Global HR Executive (part of Gem Events & Consultancy) have a simple mission, to provide…” Source: RevenueBase Database · checked Sep 21, 2026
18	Insight222	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	21 contacts →
	Indirect evidence “is a specialist professional services firm headquartered in London, UK and with employees in Europe and North America.” Source: RevenueBase Database · checked Sep 21, 2026
19	Lighterhr	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	18 contacts →
	Partial evidence “Expert HR consulting and support services for you to develop the performance you want in your business and address the issues you don’t!” Source: RevenueBase Database · checked Sep 21, 2026
20	Catalyst Partners	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	16 contacts →
	Indirect evidence “We are global change-makers.” Source: RevenueBase Database · checked Sep 21, 2026
21	Macmillan Davies	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	15 contacts →
	Partial evidence “Sourcing and recruiting the best HR talent since 1979 With offices in London, Manchester and Birmingham we have a strong regional presence across the UK and EMEA, with a growing…” Source: RevenueBase Database · checked Sep 21, 2026
22	Working Futures	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	14 contacts →
	Indirect evidence “We care about the People that work for business as we believe that’s where the real competitive advantage lies and, let’s face it, where the magic happens.” Source: RevenueBase Database · checked Sep 21, 2026
23	GO Enterprise HR Software	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	11-50	14 contacts →
	Partial evidence “Go Enterprise HR: The Ultimate All-in-One HR Solution for Growing Businesses HR doesn’t have to be complicated.” Source: RevenueBase Database · checked Sep 21, 2026
24	Open ORG	Indirect evidence	London, United KingdomHQ checked Sep 21, 2026	1-10	14 contacts →
	Indirect evidence “of startup People teams save hours every day with Open Org.” Source: RevenueBase Database · checked Sep 21, 2026
25	HR Ninjas	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	1-10	13 contacts →
	Partial evidence “Professional network for people working in HR.” 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: HR systems. 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 HR systems.
Partial evidence: Its own public description names part of HR systems, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name HR systems. 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 451 HR systems based in London, United Kingdom

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HR systems based in London, United Kingdom at a glance

As of Sep 21, 2026

16.8%Verified-email coverage

13.9Average contacts per company

1-10Median size (employees)

100.0%Largest-city concentration · London

Sep 21, 2026Page data refreshed

Companies by employee count

1-10

345

11-50

51-200

201-500

501-1,000

1,001-5,000

Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 451 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 HR systems, 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 London, United Kingdom whose own description of what they do matches “HR systems”. 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 HR systems), 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 HR systems, and records with no verified work email. Companies headquartered outside London 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, 1,049 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.

HR systems by metro in the United Kingdom

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 HR systems, 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 HR systems are there based in London, United Kingdom?

RevenueBase identified 451 HR systems headquartered in London, 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?

NGA Human Resources, An Alight Company, headquartered in London, tops this list with the largest team on record.

Which city has the most HR systems?

London leads with 451 headquartered companies, followed by Manchester (54) and Bristol (30).

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 1,049 verified decision-maker contacts tracked across these 451 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.

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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.