Telecommunications Companies in Cardiff: 163 Active Firms (2026)
Telecommunications companies in Cardiff provide connectivity, voice, data and network services for businesses across the city region.
Buying is usually split between IT, operations and facilities or property teams rather than a single telecoms desk. Cardiff-based operators tend to sell recurring connectivity, voice, mobile and managed-communications contracts to small and mid-market businesses, public-sector sites and property operators, with engineers handling installation and support desks absorbing service issues. Engagements are typically practical and service-led: migration from legacy lines, fibre provisioning, call routing, mobile estate management and network integration across multiple sites. For researchers, the useful split is between asset-owning network operators, resellers that package carrier services, and integration-led providers that stay close to the customer estate.
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Cardiff has 163 actively trading telecommunications companies, making this a compact city-region cohort rather than a broad national carrier base. Reported employment across the cohort is 437 people, which points to a market made up largely of lean operating teams rather than large network workforces. The commercial centre of gravity appears to sit in regional business services: recurring contracts, installation engineering and support-led account management for customers in Cardiff, South Wales and wider UK markets. Scale is uneven, with most firms below upper mid-market revenue thresholds and only a small revenue-ranked tail.
Operating constraints vary by model. Firms that resell fixed-line, mobile or fibre services are exposed to carrier contract terms, service-level commitments and customer-notification duties, while network operators face heavier obligations around access, resilience, faults and installation work. Public-sector and property-site customers add procurement, safeguarding and continuity requirements; installation-led providers also need field engineering processes that hold up across shared buildings and business parks. The Cardiff market therefore looks less like a single regulated product category and more like a chain of communications services, with liability passing between network owner, reseller, integrator and support desk.
Future movement appears likely to be shaped by contract churn, carrier dependency and the cost of maintaining service quality, rather than by a sudden wave of fresh network builds. Smaller resellers tend to compete on responsiveness and local account knowledge, but that model can become exposed when customers prefer bundled connectivity, voice, mobile and managed network support through consolidated supplier panels. Larger revenue-ranked operators may absorb more regional demand from businesses that want nearby support, while early-commercial entrants test narrower niches around installation, mobile estate management and communications infrastructure administration.
What’s in the file
One row per company, 50+ columns — everything below plus each company’s verified directors, from Companies House filings.
Company data
Verified directors — included
163
Active firms
2026
3
£5M-plus firms
reported turnover
41
Since 2022
new incorporations
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Key facts
About 1% of the trading cohort reports turnover above £5M (3 of 163 firms) — the rest sits below that revenue band.
25% of the cohort was incorporated since 2022 (41 firms), so a sizeable share is in its first few filing cycles.
Cardiff telecoms providers sit close to business resilience, covering connectivity, voice, data links and network support for local employers.
Procurement tends to focus on uptime expectations, support cover, contract terms and escalation routes because outages affect offices, call centres and field teams.
The local segment appears weighted towards managed connectivity, business voice and network service models rather than national-carrier-scale infrastructure.
Infrastructure-light and reseller models can make turnover and payroll move unevenly, so service ownership is often as important as headline pricing.
Top Cardiff Telecommunications companies
Financial sub-scores
Computed from 3 filingsProvides IT support and managed IT services for businesses, including helpdesk support, server and Microsoft 365 solutions, backup and security. Supplies telecoms, VoIP and broadband services,…
Serves businesses and organisations across sectors, particularly in Wales, including clients needing office technology suppliers for IT, telecoms, managed print, broadband, audio-visual equipment and…
Financial Health
StrongStrong · Growing, Hiring · 18% CAGR over 2y
Location
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Financial sub-scores
Computed from 5 filingsProvides telecommunications consultancy and technology services including MVNO and MVNE support, private 5G/LTE network deployment, IoT connectivity, asset and vehicle tracking solutions, and mobile…
Serves telecoms operators, MVNOs/MVNEs, IoT businesses, event organisers, local authorities, and organisations needing private 5G/LTE connectivity for rural sites, vehicles, smart cities, agritech,…
Financial Health
StableStable
Location
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Financial sub-scores
Computed from 4 filingsProvides business communications and IT services including VoIP and hosted telephony, phone systems, broadband and leased line connectivity, managed Wi‑Fi and SD‑WAN, mobile solutions, Microsoft 365…
Sells to UK businesses needing integrated communications, connectivity, IT support and cyber security. Serves organisations seeking business telephony, broadband, mobile, Microsoft 365, IoT and…
Financial Health
DistressedDistressed
Location
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Financial sub-scores
Computed from 5 filingsFinancial Health
StrongStrong
Location
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Financial sub-scores
Computed from 5 filingsFinancial Health
DistressedDistressed
Location
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Financial sub-scores
Computed from 5 filingsServes mobile network operators, telecom service providers, and RAN hardware/software vendors involved in 2G, 3G, 4G and 5G network deployments.
Financial Health
HealthyHealthy · -7% CAGR over 4y
Location
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Financial sub-scores
Computed from 5 filingsProvides dedicated internet connectivity, cloud hosting, and data centre colocation services for businesses. Offers high‑speed leased line internet access, cloud infrastructure, and hosting solutions…
Serves businesses of all sizes, from start-ups to large publicly traded companies, plus technology partners selecting services for their own clients.
Financial Health
WeakWeak · 0% CAGR over 1y
Location
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Financial sub-scores
Computed from 5 filingsFinancial Health
HealthyHealthy
Location
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Computed from 5 filingsFinancial Health
HealthyHealthy · 0% CAGR over 4y
Location
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Financial Health
N/AN/A
Location
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Financial sub-scores
Computed from 5 filingsFinancial Health
WeakWeak · Hiring · 32% CAGR over 4y
Location
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Financial Health
N/AN/A
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Computed from 4 filingsProvides safety‑critical communication systems and equipment including digital two‑way radio hire, GSM‑R and tunnel radio installations, proximity warning systems, noise‑protective headsets, body…
Serves B2B customers in construction, rail, tunnelling and infrastructure projects, including site managers, contractors, machine operators and security teams needing safety-critical communications…
Financial Health
WeakWeak · -4% CAGR over 3y
Location
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Financial sub-scores
Computed from 5 filingsFinancial Health
DistressedDistressed
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed · 0% CAGR over 4y
Location
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Financial Health
N/AN/A
Location
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Financial sub-scores
Computed from 3 filingsFinancial Health
StrongStrong
Location
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Computed from 4 filingsProvides network infrastructure and communications installation services, including Cat5e and Cat6 data cabling, LAN and WAN setup, fibre optic links, wireless networks, IP CCTV systems, and aerial…
Serves businesses of all sizes needing communications, network cabling, CCTV, wireless and connectivity infrastructure, with additional aerial installation services for domestic and commercial…
Financial Health
HealthyHealthy · Hiring · 8% CAGR over 3y
Location
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Computed from 5 filingsFinancial Health
HealthyHealthy · 0% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed
Location
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Computed from 5 filingsProvides IT services including managed IT support, cloud infrastructure design, cybersecurity, and business connectivity. Implements and supports Microsoft 365, Azure, Dynamics and Sage systems, and…
Serves businesses and charities, including construction, distribution, manufacturing, warehousing, retail, SaaS, commercial property and other service-sector organisations.
Financial Health
StrongStrong · Growing, Hiring · 86% CAGR over 4y
Location
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Computed from 5 filingsDevelops and provides Microsoft Teams telephony and unified communications software. Its C360 platform integrates calling, contact centre functions and system integrations, with tools for monitoring…
Sells to businesses and organisations using Microsoft Teams, from small teams adopting Teams calling to growing and complex, regulated or mission-critical environments needing contact centre, voice…
Financial Health
HealthyHealthy · Hiring · 14% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed
Location
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Computed from 5 filingsFinancial Health
HealthyHealthy · Hiring · 15% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed · 0% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed
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Computed from 4 filingsFinancial Health
DistressedDistressed
Location
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Computed from 2 filingsFinancial Health
DistressedDistressed
Location
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Computed from 2 filingsFinancial Health
DistressedDistressed
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Computed from 5 filingsFinancial Health
DistressedDistressed · 0% CAGR over 5y
Location
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Financial Health
N/AN/A
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Computed from 5 filingsFinancial Health
StrongStrong · 71% CAGR over 3y
Location
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Financial sub-scores
Computed from 4 filingsDistributes pay‑as‑you‑go SIM cards from major UK mobile network providers, supplying retailers such as convenience stores, mobile phone dealers, forecourts and independent supermarkets, and offering…
Serves UK consumers seeking pay-as-you-go SIM cards and supplies retail channels including high street shops, independent convenience stores, mobile dealers, forecourts, gift and vape shops, and…
Financial Health
DistressedDistressed · -21% CAGR over 3y
Location
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Computed from 5 filingsFinancial Health
StableStable · 0% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
WeakWeak · -68% CAGR over 4y
Location
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Computed from 5 filingsProvides business telecommunications services including telephone systems, cloud VoIP, business mobile contracts, broadband and dedicated internet access. Supplies IP phones, Wi‑Fi and network…
Serves businesses in South Wales, particularly SMEs with office, remote or hybrid teams needing managed telecommunications and connectivity support.
Financial Health
HealthyHealthy · Hiring · 14% CAGR over 4y
Location
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Computed from 5 filingsProvides business telecommunications and IT services, including VoIP and on‑premise phone systems, business broadband and leased lines, mobile packages, network design, cloud services, IT…
Serves business customers in South Wales and South West England, including organisations needing telecoms, broadband, mobile, phone system and managed IT support across office-based and remote teams.
Financial Health
StableStable · Hiring · 24% CAGR over 4y
Location
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Computed from 4 filingsProvides data centre and business continuity hosting, virtual private cloud servers, and high‑speed internet connectivity. Offers data transit services, private fibre networks between sites, and WAN…
Serves businesses in South Wales and Cardiff needing IT continuity, high-bandwidth connectivity and cloud infrastructure, including media companies, data centres and multi-branch organisations with…
Financial Health
StrongStrong · Growing · 0% CAGR over 3y
Location
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Computed from 4 filingsProvides managed IT support and business technology services including Microsoft 365 and Azure cloud management, cybersecurity, backup and disaster recovery, network cabling, business telephony,…
Serves SMEs and other organisations across South Wales, Cardiff, Swansea, Newport and Bristol that need outsourced or supplementary IT support for business operations.
Financial Health
HealthyHealthy · -78% CAGR over 3y
Location
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Computed from 5 filingsProvides business telecommunications services including cloud telephony and hosted phone systems, Microsoft Teams calling integration, broadband and fibre internet, leased lines, call recording,…
Serves B2B organisations in the UK, especially small businesses and SMEs, as well as corporates, call centres, international charities and government bodies. Also targets partners and IT…
Financial Health
HealthyHealthy · Hiring · 5% CAGR over 4y
Location
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Computed from 5 filingsProvides business telecommunications systems and services, including VoIP and hosted telephony, on‑premise PBX systems, SIP trunking, unified communications, networking and wireless solutions, data…
Serves businesses and organisations, from small offices to large enterprises, that need control or outsourced management of their telecommunications infrastructure, including those preparing for the…
Financial Health
StableStable · 0% CAGR over 4y
Location
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Computed from 5 filingsProvides managed IT support, cloud services, VoIP telephony, and cyber security services for businesses. Offers 24/7 security monitoring, Cyber Essentials certification support, penetration testing,…
Serves SMEs in South Wales, Bristol and surrounding areas, including charities, third-sector organisations, environmental firms, financial services, manufacturers, professional services, and…
Financial Health
StrongStrong · Growing, Hiring · 5% CAGR over 4y
Location
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Computed from 5 filingsProvides managed IT and telecoms services for businesses, including remote helpdesk support, network infrastructure installation, fibre and broadband connectivity, VoIP phone systems, cybersecurity…
Serves businesses and organisations with internal user bases, targeting directors, company secretaries, office managers and operational leads responsible for IT, telecoms, connectivity, print and…
Financial Health
WeakWeak · 0% CAGR over 4y
Location
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Computed from 5 filingsProvides business telecommunications services including installation and support of telephone systems, cloud-hosted telephony, VoIP migration, SIP trunking, broadband and leased line connectivity,…
Serves businesses of varying sizes and NHS organisations that need business telephony, connectivity, mobile SIM and legacy phone system support.
Financial Health
StableStable · Hiring · 26% CAGR over 4y
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N/AN/A
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Computed from 5 filingsProvides business telecoms and connectivity services including unified communications, VoIP and fibre broadband. Supplies and supports digital print and multifunction devices, installs CCTV and…
Serves B2B customers, including businesses and organisations across Wales and the UK, with emphasis on Cardiff-area firms needing workplace telecoms, connectivity, print, security, energy and…
Financial Health
HealthyHealthy · Hiring · 15% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
HealthyHealthy
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Computed from 5 filingsProvides telecommunications infrastructure services including overhead cable installation, fibre splicing, network build and maintenance, vacuum excavation, civil engineering, and surveying and…
Sells to telecoms operators, infrastructure contractors, and civil engineering firms needing network build, installation, and maintenance services. Also serves telecoms and civil engineering…
Financial Health
StrongStrong · Growing, Hiring · 30% CAGR over 4y
Location
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Computed from 5 filingsInstalls and maintains communication infrastructure including structured copper and fibre optic data cabling networks and hosted cloud-based telephone systems. Provides telecommunications…
Serves businesses and public sector organisations needing telecoms and data cabling installations, including offices, schools, hospitals and public service stations. Targets end users from…
Financial Health
StableStable · 0% CAGR over 4y
Location
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Computed from 5 filingsProvides managed IT support, telecoms and broadband services for businesses. Offers cloud systems and Microsoft 365 support, cybersecurity services, network cabling and infrastructure, web and…
Serves businesses of all sizes and public/not-for-profit organisations, with sector focus on education, legal, local government, healthcare, real estate, financial, media, manufacturing and retail…
Financial Health
HealthyHealthy · Hiring · 6% CAGR over 4y
Location
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How Cardiff Telecommunications companies work and how to sell to them
What they do
Cardiff telecommunications firms usually earn through recurring service charges, resale margin, installation fees and managed-support retainers. Connectivity and voice contracts tend to be priced per circuit, user, handset, site or service bundle, with project fees added for migration, cabling, configuration and number-management work. Asset-owning operators carry more capital and maintenance risk; resellers depend on upstream carrier pricing and service levels; integration-led providers monetise proximity to the customer estate. The product shape is therefore a mix of infrastructure access, configuration work, support process and account management, rather than a single software or hardware sale.
Who they sell to
Most sell to organisations that treat communications as operational plumbing: local SMEs, multi-site businesses, public-sector locations, landlords, serviced offices and regional infrastructure customers. The buyer is typically an IT manager, operations lead, facilities manager, finance director or procurement contact, with senior sign-off when a contract affects business continuity or several sites. Simple voice, mobile and broadband moves can close through direct sales or account management. Network integration, public-sector supply and property-site work tends to involve longer scoping, site surveys, supplier checks and formal procurement, especially where service levels and fault response are part of the decision.
What they buy
Most Cardiff telecommunications firms tend to spend on systems that reduce service friction and protect margin: CRM, quoting, billing, contract management, service desk, network monitoring, field-service scheduling and customer communications. Resellers also need carrier-order management, commission tracking and reporting that reconciles supplier costs against customer charges. Installation-led providers buy vehicles, test equipment, cabling supplies, health and safety support, insurance, training and subcontracted engineering capacity. Across the sector, common service purchases include accounting, legal review of customer terms, cybersecurity, recruitment for engineers and support staff, and marketing aimed at local business buyers rather than broad consumer audiences.
Why and how to sell to them
Telecommunications buyers tend to evaluate suppliers when churn rises, support queues lengthen, carrier pricing changes, or a run of installations exposes weak coordination between sales, engineering and billing. Funding is usually a less visible trigger than contract wins, new public-sector eligibility, a larger property-client mandate, or hiring in engineering and service operations. Outbound messaging works better when it is tied to leakage and continuity: fewer missed renewals, clearer service-level reporting, cleaner billing, faster provisioning, reduced truck rolls or lower complaint volumes. Generic productivity claims are easier to ignore in a sector where small process errors can create visible customer disruption.
How this list is built
Data sources
This list is built from UK Companies House filings, XBRL accounts data, and semantic analysis of each company's public website. Revenue and headcount figures come from the most recent filed accounts; where the company has not filed, values are estimated using a model trained on filed history and peer benchmarks and are labelled as estimates.
Classification
Rather than relying solely on SIC codes, Firmbase classifies each company semantically: the company's website is crawled, an AI model reads what the company actually sells, and the company is placed into the relevant industry and subsectors. SIC codes are used as one signal but not the only one. This means a company that registered under a generic SIC code but pivoted into (for example) fintech is correctly identified as fintech, not as its original SIC category.
Freshness
The underlying company data is refreshed from Companies House continuously; filings appear in the list within days of submission. The curated list ordering is regenerated when the underlying data moves meaningfully (company count changes by more than 5%, a new company enters the top-ranked segment, or the filed-revenue numbers for the top firms change). You can see the last-updated timestamp near the top of the page.
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Frequently asked questions
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