Independent list · re-checked September 28, 2026 · published by Primortul LLC

SEO companies in California

4 of the 13 SEO companies on this list are based in California (CA), in San Diego, San Francisco, Simi Valley, Los Angeles. The other 9 are based elsewhere on the list. Who leads them, the work they can show, and why each one made the list. This is the list, not a ranking of the state. Nobody pays to be ranked.

  1. 01 on the list · San Diego, CA

    Siege Media

    Since 2012 · 51–200 people

    Siege Media is a content marketing and SEO agency founded in San Diego in August 2012 by Ross Hudgens, with offices in Austin, Chicago, New York and San Francisco and roughly 80 staff. It produces search-targeted content, design assets, digital PR and generative-engine optimisation for fintech, e-commerce, SaaS and health brands, and states its work is worth about $12.4 million a month in client traffic value. It is privately held and a 2022 Inc. 5000 honoree.

    Why it’s hereInc. 5000 honoree with a published client list including Zillow, Airbnb, HubSpot and TransUnion and a practice built entirely on organic search.

    Who leads itRoss Hudgens, Founder / CEO.

    Estimated cost

    Estimated: $3,000–$10,000/mo, typical for US SEO retainers; not a quote.

    Typical industry estimate, not a quote from any firm on this list.

    SEO-driven content marketing · generative-engine optimisation · digital PR · SEO consulting · design

  2. 02 on the list · San Francisco, CA

    Victorious

    Since 2013

    Victorious is an SEO agency founded in 2013 and based in San Francisco, with staff across Austin, Boston, Chicago, Denver, Washington, Los Angeles, New York, Philadelphia, Phoenix, Portland, San Diego and Seattle. It provides on-page and technical SEO, keyword research, audits, migrations, link building, answer-engine optimisation for ChatGPT, Perplexity and Google AI Overviews, and content, and reports serving more than 1,050 brands. It is privately held and a 2022 Inc. 5000 honoree.

    Why it’s hereNamed SEO Agency of the Year five times, including Search Engine Land's Global SEO Agency of the Year and Best Large Agency at the 2022 US Search Awards.

    Who leads itMichael Transon, CEO.

    Estimated cost

    Estimated: $3,000–$10,000/mo, typical for US SEO retainers; not a quote.

    Typical industry estimate, not a quote from any firm on this list.

    SEO · answer-engine optimisation · technical SEO and migrations · link building · content strategy

  3. 06 on the list · Simi Valley, CA

    Bruce Clay Inc.

    Since 1996

    Bruce Clay Inc. is an SEO consultancy founded in January 1996 by Bruce Clay and headquartered in Simi Valley, California, with separately owned affiliate offices in Japan, India, Australia, Singapore and Italy. It provides SEO consulting, training courses, PPC management, content and its own analysis tools, and its founder wrote 'Search Engine Optimization All-in-One For Dummies' and the Search Engine Relationship Chart. The firm is privately held and its technical staff average more than ten years' experience.

    Why it’s hereFounded in 1996, one of the first SEO firms in the United States and the source of widely used industry training and reference material.

    Who leads itBruce Clay, Founder.

    Work they can showNational Drug Screening. SEO strategy credited with a 166% traffic increase. Industrial equipment supplier (unnamed). SEO work credited with a 72% increase in revenue from organic search. B2B SaaS startup (unnamed). SEO program that quadrupled website traffic in 17 months.

    Estimated cost

    Estimated: $3,000–$10,000/mo, typical for US SEO retainers; not a quote.

    Typical industry estimate, not a quote from any firm on this list.

    SEO consulting · SEO training · PPC management · content development · SEO tools

  4. 13 on the list · Los Angeles, CA

    Coalition Technologies

    Since 2009 · 201–500 people

    Coalition Technologies is an SEO and web design agency founded in 2009 by brothers Joel Gross and Jordan Brannon and headquartered at 515 S Flower Street in Los Angeles, with more than 250 full-time staff. It offers SEO, AI-search optimisation, PPC, Shopify and BigCommerce development, email and conversion optimisation, and publishes more than 860 case studies including Microsoft, Roku, PayPal and Walmart. It is a Google Premier Partner and Shopify Premier Partner and privately held.

    Why it’s hereA 250-person independent SEO firm with 160-plus Clutch reviews averaging 4.8 and a 2025 Best of Clutch digital marketing award.

    Who leads itJoel Gross, Founder and CEO.

    Published pricing
    • Minimum project on Clutch$1,000+
    • Hourly rate on Clutch$50 - $99 / hr

    SEO · AI SEO and generative-engine optimisation · e-commerce web design · PPC · conversion optimisation

Compare states and cities

Free · no obligation

Describe the job. One SEO company writes back.

Tell us what you sell, what is not working, and what done looks like. We read it and ask one provider — from this list, or from the publisher’s bench — to contact you within a business day. Asking is free. You do not have to hire them. Nobody else gets what you wrote.

When

Sending shares what you wrote with the one provider we match you to. How that works.

The same list, elsewhere
Other lists in the US