Top 5 B2B Managed Data Cleansing and Enrichment Service Providers in the UK

You have decided to outsource. The quotes that came back look nothing alike. That is because they describe different work:

• A bureau runs a process on a file you send.

• A team phones records to confirm them.

• A partner defines what the data must contain before any processing starts.

Knowing which model you are buying makes outsourced data cleansing quotes comparable.

This guide compares five managed data cleansing service providers. They are IMG (Intermedia Global Ltd), GSA Marketing, Anteriad, Integra Data Solutions, and GCL B2B. Each is an option for UK teams hiring B2B marketing data cleansing service providers or B2B marketing data enrichment service providers.

What Does A Managed Data Cleansing Service Include?

It removes duplicates, fixes invalid records, and updates outdated details. It then enriches what is missing. In outsourced data cleansing, who verifies the result, and how, depends on the model. There are three models:

• Consultative: a partner defines the requirement, then delivers it.

• Telephone-verified: people call records to confirm them, producing telephone-verified B2B data.

• Enterprise bureau: a fixed process runs on the file you send.

Judge each provider on five criteria:

• Who performs the verification, and by what method.

• Whether the engagement is one-off or continuous.

• Source breadth.

• Whether scope covers specifying the requirement or only executing it.

• UK GDPR, TPS and CTPS handling, which decides whether you receive GDPR compliant B2B data.

Two quotes from managed data cleansing service providers can describe entirely different work. That is why price comparison is misleading here.

The Top 5 Managed B2B Data Cleansing Providers

Five are compared below, grouped into four models:

• Consultative: IMG (Intermedia Global Ltd).

• Telephone-verified: GSA Marketing and GCL B2B.

• Platform plus managed service:

• Enterprise bureau: Integra Data Solutions.

Seeing the model first makes each entry easier to read. B2B data services in the UK look crowded until you sort them this way. Most managed data cleansing service providers and B2B data enrichment service providers fit one of these shapes.

1. Intermedia Global Ltd (IMG)

IMG (Intermedia Global Ltd) is a London-based B2B marketing consultancy. Its engagement starts by defining what the data must contain, not by processing what was sent. That is the distinction that matters most on this list.

IMG (Intermedia Global Ltd) was ranked 109th in the FT1000 Europe’s Fastest-Growing Companies 2026. It was also named among the top 10 UK agencies in the B2B Marketing UK Agencies Benchmarking Report 2026.

It traces its origins to 2003 and works from London and Bedford. Clients include HSBC, Shell, Broadcom and other mid-to-large B2B enterprises. The managed model covers seven services:

• Data quality audit: establishes what is accurate, outdated, duplicated, incomplete, or missing before any processing is scoped.

• B2B data cleansing: the B2B marketing data cleaning consultants fix duplicate accounts and contacts, invalid and incomplete records, inconsistent fields, and outdated employment information.

• CRM data enrichment: the B2B marketing data enrichment consultants add seniority, function, company size, revenue, industry, sub-industry, geography, technology usage and account hierarchy.

• Data validation services: every update is checked for accuracy and GDPR compliance before it returns to your CRM.

• Waterfall data enrichment: one source identifies the account. A second fills missing contact details. A third adds buying-group members. A specialist source adds geographic or sector depth.

• Bespoke B2B database build: specified from the marketing requirement.

• GDPR compliant B2B data: sourced only from trusted, compliant sources.

Steve Kemish, CEO of IMG, describes the work as “deliberately unglamorous: audit what’s there, fill in what’s missing, verify it properly, and hand it back in a state a marketing team can trust.” The service is modular. Use the whole lifecycle or one component alongside your existing teams and licences.

Best for: organisations that want the requirement defined as well as delivered.

Not for: a fixed-scope file cleanse where the spec is already settled.

2. GSA Marketing

GSA Marketing is the trading name of GSA Business Development Ltd. Managing director Jonathan Silverman leads the business. Its B2B data services in the UK cover data building, cleaning, enrichment and data validation services.

As an outsourced data cleansing option, GSA offers one-off or regular cleaning. Records are validated by phone and duplicates are removed. Opt-out screening covers the telephone and mailing preference services, including CTPS.

For a bespoke B2B database build, GSA pairs an AI-powered data platform with an in-house research team. Consent can be recorded on calls with date and time stamps. Multilingual teams are based in Hungary, Spain and Colombia.

Suited to: mid-sized UK and international campaigns where verified contact accuracy matters over volume.

Not for: enterprise-scale datasets or continuous automated refresh.

3. Anteriad

Anteriad began in 2000 as MeritDirect, a B2B list brokerage, and took its current name in 2022. Its UK company, Anteriad Global Limited, was incorporated in 2013. Madrid-based BNZSA, acquired in 2023, now trades under the Anteriad brand.

Among B2B marketing data enrichment service providers, Anteriad is platform-led. Its Marketing Cloud can cleanse and append CRM files with firmographic, demographic and intent data. It connects to CRMs such as Salesforce and HubSpot.

Anteriad reported reach of more than 414 million contacts in a November 2025 press release. It does not describe its method as waterfall data enrichment, citing a multisource database instead. EMEA phone teams log GDPR consent per call.

Suited to: global enterprise programmes needing scale across regions.

Not for: UK-only mid-market work, where the engagement model is heavier than required.

4. Integra Data Solutions

Integra Data Solutions Ltd (Companies House 12145011) is based in Chelmsford, Essex. Chris Feasey and James Neale founded it in February 2020. Its consultancy covers forecasting, segmentation and data profiling services.

Its BusinessDB file lists over 6.5 million UK companies, 17 million contacts and 12 million decision-makers, with TPS and CTPS flags. Records are keyed to the Unique Property Reference Number. This links business, property and home-mover data at address level.

Integra’s answer to “What does a managed data cleansing service include?” is a four-step process. It starts with a data quality audit, then de-duplication, standardisation and validation of email, phone and postal data.

Suited to: enterprises wanting one supplier across data and campaign delivery.

Not for: teams who want the source mix chosen per requirement.

5. GCL B2B

GCL B2B Limited (Companies House 03015169) was incorporated in 1995, though GCL dates its trading to 1990. Its office is on Charlotte Street, Birmingham. It describes a pan-EMEA focus across IT, telecoms, logistics and professional services.

GCL says its GDPR compliant B2B data comes from primary sources that are audited and televalidated. Among managed data cleansing service providers, it combines de-duplication, tele-validation and AI-based tools, in multiple languages.

GCL publishes indicative prices for telephone-verified B2B data. Televalidated senior contacts from existing sources start from £650 per 1,000. Bespoke research can reach £15 per contact. It states full TPS and CTPS compliance.

Suited to: programmes where data work and outbound calling run together.

Not for: data work independent of a calling campaign.

How to Scope a Managed Data Engagement

Before you shortlist managed data cleansing service providers, run a data quality audit. It tells you what exists before anyone changes it.

Then ask every one of the B2B marketing data cleaning service providers and B2B marketing data enrichment service providers on your list for its model, verification method, refresh cadence and licence term in writing.

Use the table to compare B2B data services in the UK by model. If your spec is already settled, read the enterprise bureau row first.

Making Managed Data Work for Your Next Campaign

Good data is a means. The goal is ABM, complete buying groups, personalisation at scale, consistent multi-channel activation and AI readiness. None of those works on records that are duplicated, thin, or out of date.

Outsourced data cleansing is straightforward to process. Every one of the managed data cleansing service providers here can run a process. The value sits in who decides what the data needs to contain.

Pick the model that fits your requirements from the B2B data services in the UK, then hold the provider to the contract checks above.