Company lists · Data refreshed September 2026
Top 25 Web SEO companies based in Spain
RevenueBase identified 734 web SEO companies headquartered in Spain as of September 2026 and tracks 2,650 professional contacts across them, including 381 with verified work emails. Madrid is the largest hub.
This list covers web SEO companies 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 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.
The 25 largest web SEO companies based in Spain
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 108 contacts → | ||||
Strong evidence “En nuestra agencia SEO en Barcelona somos unos apasionados del posicionamiento web.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 2 | 38 contacts → | ||||
Partial evidence “Esta empresa se creó para dar respuesta a una necesidad cada vez más demandada: el posicionamiento web.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 3 | 38 contacts → | ||||
Indirect evidence “Keyweo is a digital marketing agency founded in 2018 and based in Barcelona.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 4 | 31 contacts → | ||||
Partial evidence “de páginas web accesibles.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 5 | 31 contacts → | ||||
Indirect evidence “Since 2001, we've been boosting the online discoverability of leading international companies and media outlets.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 6 | 25 contacts → | ||||
Partial evidence “Joan Boluda, Consultor de Marketing OnlineEspecializado en Posicionamiento Natural (SEO), Pago Por Clic (PPC), Redes Sociales (SMO) y Email Marketing.Si tienes claro tu plan de…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 7 | 23 contacts → | ||||
Partial evidence “Convertix is an International SEO & Performance Marketing Agency with offices in Madrid and Milan serving clients in 20+ markets and 10+ languages.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 8 | 22 contacts → | ||||
Strong evidence “Posicionamiento Web SEO, Marketing Online y diseño de páginas web en Marbella.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 9 | 21 contacts → | ||||
Indirect evidence “Liten Lemon es una agencia de marketing digital ubicada en Madrid, España.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 10 | 20 contacts → | ||||
Strong evidence “Sembi Communication is a Digital Marketing Agency experts in SEO (Search Engine Optimization),(Search Engine Marketing), Media Digital Content, Web Design, Community Manager &…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 11 | 19 contacts → | ||||
Indirect evidence “En YoSEOMarketing, somos la agencia líder en transformación digital, especializada en posicionamiento y resultados sostenibles.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 12 | 17 contacts → | ||||
Indirect evidence “Websdirect es una empresa que ofrece soluciones completas para internet desde 1998, nuestras oficinas se encuentra en Madrid, España.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 13 | 16 contacts → | ||||
Strong evidence “Positio, agencia de marketing de contenidos especializada en posicionamiento SEO y SEM-PPC, analítica web, Social Media y blogging.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 14 | 15 contacts → | ||||
Partial evidence “Services of Digital Strategy, Online Marketing and Development of websites and applications in web environment and mobile applications.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 15 | 15 contacts → | ||||
Strong evidence “Seocoaching es una empresa especializada en posicionamiento web con resultados comprobados y servicios SEO garantizados.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 16 | 15 contacts → | ||||
Strong evidence “Agencia de Marketing Online, Posicionamiento SEO, Local SEO, SEM, Gestión de Redes Sociales, Diseño Gráfico, Diseño Web y e-Commerce.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 17 | 15 contacts → | ||||
Strong evidence “Somos un equipo de profesionales, técnicos en informática, programadores de software, diseñadores web y técnicos en posicionamiento SEO y marketing Online con amplia experiencia…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 18 | 14 contacts → | ||||
Partial evidence “Novaigrup, agencia de ingeniería web y marketing en Internet.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 19 | 13 contacts → | ||||
Indirect evidence “Estudio34 is an online marketing agency based in Barcelona (Spain) that provides digital marketing services to businesses that either need to improve their online visibility or…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 20 | 13 contacts → | ||||
Partial evidence “In Optimanova we understand Web Optimisation as a way to take the best advantage from your website.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 21 | 12 contacts → | ||||
Indirect evidence “En Grouber Marketing, te ayudamos con una estrategia específica para tu negocio.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 22 | 11 contacts → | ||||
Partial evidence “Softalian es una agencia de SEO y de marketing online.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 23 | 11 contacts → | ||||
Partial evidence “Fast Digital WS es una agencia de Marketing Online especializada en el diseño y gestión de estrategias de marketing online, creación de webs corporativas y consultoría.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 24 | 11 contacts → | ||||
Indirect evidence “AGENCIA SEOCLIC Somos una Agencia especializada en posicionamiento online, y que cubrimos diferentes servicios relacionados con el Marketing Digital.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 25 | 10 contacts → | ||||
Partial evidence “De la mà d’Eva Olivares i Xevi Sañé neix la primera agència 100% SEO a Girona.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
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: web SEO companies. 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 web SEO companies.
- Partial evidence
- Its own public description names part of web SEO companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name web SEO companies. 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 734 web SEO companies based in Spain
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Web SEO companies based in Spain at a glance
As of Sep 21, 2026Companies by employee count
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 734 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 web SEO companies, 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 “web SEO companies”. 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 web SEO companies), 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 web SEO companies, 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, 381 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.
Web SEO companies by metro
- Web SEO companies in Madrid131
- Web SEO companies in Barcelona85
- Web SEO companies in Valencia35
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 web SEO companies, 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 web SEO companies are there based in Spain?
RevenueBase identified 734 web SEO companies 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?
Bigseo, headquartered in Barcelona, tops this list with the largest team on record.
Which city has the most web SEO companies?
Madrid leads with 131 headquartered companies, followed by Barcelona (85) and Valencia (35).
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 381 verified decision-maker contacts tracked across these 734 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.
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