Company lists · Data refreshed September 2026

Top 17 Enterprise fiber providers based in Spain

RevenueBase identified 92 enterprise fiber providers headquartered in Spain as of September 2026 and tracks 2,521 professional contacts across them, including 334 with verified work emails. Madrid is the largest hub.

This list covers enterprise fiber providers headquartered in Spain, 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 28, 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 28, 2026 86% judged on-target in blind review
92Companies
2,521Contacts tracked
334Verified emails
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The 17 largest enterprise fiber providers based in Spain

Ranked by team size
Top 17 of 92 enterprise fiber providers based in Spain, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to enterprise fiber providers: 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.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceMadrid, SpainHQ checked Sep 28, 20261,001-5,0001,182 contacts →

Indirect evidence

“UFINET is a Latin American carrier of carriers providing high-quality solutions in the wholesale telecom market.”

Source: RevenueBase Database · checked Sep 28, 2026
2Indirect evidenceBarcelona, SpainHQ checked Sep 28, 202651-200298 contacts →

Indirect evidence

“Adamo is a telecom operator with Swedish origin operating in Spain since 2007.”

Source: RevenueBase Database · checked Sep 28, 2026
3Indirect evidenceMadrid, SpainHQ checked Sep 28, 2026201-500294 contacts →

Indirect evidence

“As the world’s needs for uninterrupted global interconnectivity continue to rise, we are preparing the road ahead.”

Source: RevenueBase Database · checked Sep 28, 2026
4Indirect evidenceAlcobendas, SpainHQ checked Sep 28, 2026201-500157 contacts →

Indirect evidence

“lyntia is the leading wholesale optic fibre operator in Spain and Portugal, providing robust, flexible and sustainable connectivity solutions for the Telco and Cloud sector.”

Source: RevenueBase Database · checked Sep 28, 2026
5Indirect evidenceAlicante, SpainHQ checked Sep 28, 2026201-500132 contacts →

Indirect evidence

“Cableworld es la compañía de servicios de telecomunicaciones por fibra óptica líder en en sus zonas de influencia, en la que ofrecemos de manera integrada servicios de Internet…”

Source: RevenueBase Database · checked Sep 28, 2026
6Indirect evidencePozuelo De Alarcón, SpainHQ checked Sep 28, 202611-5030 contacts →

Indirect evidence

“Onivia es el operador mayorista de fibra óptica independiente y neutral, que está transformando el mercado de las telecomunicaciones en España.”

Source: RevenueBase Database · checked Sep 28, 2026
7Indirect evidenceMadrid, SpainHQ checked Sep 28, 202651-20026 contacts →

Indirect evidence

“Somos un operador de red que ofrece servicios mayoristas de acceso FTTH y otros servicios de conectividad sobre tecnología de fibra.”

Source: RevenueBase Database · checked Sep 28, 2026
8Indirect evidenceBarcelona, SpainHQ checked Sep 28, 202611-5021 contacts →

Indirect evidence

“En Connectivity ofrecemos servicios de conectividad personalizados para empresas que quieren ofrecer servicios de telefonía e internet con su propia marca y para empresas que…”

Source: RevenueBase Database · checked Sep 28, 2026
9Indirect evidenceZaragoza, SpainHQ checked Sep 28, 202611-5021 contacts →

Indirect evidence

“Keynet nace en 2014 como empresa y marca como resultado de nuestra inquietud por ofrecer al mercado la más amplia línea de productos pasivos para redes de cable estructurado y…”

Source: RevenueBase Database · checked Sep 28, 2026
10Indirect evidenceMadrid, SpainHQ checked Sep 28, 202611-5015 contacts →

Indirect evidence

“Axent is a carrier-neutral wholesale operator for Telecom infrastructure services in backbone, backhaul and access connectivity.”

Source: RevenueBase Database · checked Sep 28, 2026
11Indirect evidenceRibarroja, SpainHQ checked Sep 28, 202611-5013 contacts →

Indirect evidence

“KEYFIBRE (KeyFibre Network Components, S.L.) is a company within the KeyInnovation group based in Valencia, Spain.”

Source: RevenueBase Database · checked Sep 28, 2026
12Indirect evidenceMadrid, SpainHQ checked Sep 28, 202611-508 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 28, 2026
13Indirect evidenceSondika, SpainHQ checked Sep 28, 202611-506 contacts →

Indirect evidence

“Después de casi 25 años seguimos en la vanguardia de las nuevas tecnologías, consolidándonos como una de las empresas pioneras dentro del sector.”

Source: RevenueBase Database · checked Sep 28, 2026
14Indirect evidenceMurcia, SpainHQ checked Sep 28, 20261-104 contacts →

Indirect evidence

“NIXUS ofrece soluciones en redes y telecomunicaciones avanzadas para las empresas.”

Source: RevenueBase Database · checked Sep 28, 2026
15Indirect evidenceMadrid, SpainHQ checked Sep 28, 202611-503 contacts →

Indirect evidence

“Iberfibra e Iberfibra Fibra Óptica son marcas comerciales registradas de Iberfibra Gestión de Redes de Banda Ancha S.A.”

Source: RevenueBase Database · checked Sep 28, 2026
16Indirect evidenceL' Escala, SpainHQ checked Sep 28, 202611-502 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 28, 2026
17Indirect evidenceIbiza, SpainHQ checked Sep 28, 20261-102 contacts →

Indirect evidence

“Befree Networks is a revolutionary Internet service launched in Ibiza in 2014.”

Source: RevenueBase Database · checked Sep 28, 2026

Showing 17 of 92 enterprise fiber providers based in Spain

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Enterprise fiber providers based in Spain at a glance

As of Sep 28, 2026
13.2%Verified-email coverage
27.4Average contacts per company
11-50Median size (employees)
13.0%Largest-city concentration · Madrid
Sep 28, 2026Page data refreshed

Companies by employee count

1-10
45
11-50
33
51-200
9
201-500
4
1,001-5,000
1

Email recency for this list is measured worldwide rather than for Spain, so it is reported there. Company counts and contact totals on this page are exact for Spain, over 92 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 enterprise fiber providers, 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 Spain whose own description of what they do matches “enterprise fiber providers”. 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 enterprise fiber providers), 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 enterprise fiber providers, and records with no verified work email. Companies headquartered outside Spain 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, 334 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 28, 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

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 enterprise fiber providers, 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 enterprise fiber providers are there based in Spain?

RevenueBase identified 92 enterprise fiber providers headquartered in Spain 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?

Ufinet, headquartered in Madrid, tops this list with the largest team on record.

Which city has the most enterprise fiber providers?

Madrid leads with 12 headquartered companies, followed by Barcelona (5) and Valencia (4).

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 334 verified decision-maker contacts tracked across these 92 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 28, 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.