Top BPO Service Companies in California

Between them, the 26 best-ranked of these 28 BPO service companies cover medical (7), SEO (4), property (4) and business services (3). They also list work in San Francisco. 26 of them have written a profile you can read before you get in touch.

1. 1

   

   Call24 Communications

   Virtual Assistant · Medical · Scheduling · Also in San Francisco Bay Area

   Call24 Communications runs a live telephone answering service from Pleasant Hill, California, and has served businesses in the San Francisco Bay Area since 1976.

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   Why #1: Based in Pleasant Hill, California, United States · Founded 1976, as stated on its own website, read 28 Sept 2026

   Not yet on record: client reviews, vetting.

2. 2

   

   Hartley and Associates

   Call Center · Medical · Property

   Hartley and Associates is a telephone answering and call centre service based in Santa Rosa, California.

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   Why #2: Based in Santa Rosa, California · In business 30+ years, as stated on its own website, read 5 Oct 2026

   Not yet on record: client reviews, vetting.

3. =3

   

   Direct Marketing Partners

   Direct Marketing Partners, often shortened to DMP, is a B2B contact centre in Sacramento, California that builds sales pipeline for clients.

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   Why #3 (shared): Based in Sacramento, California · In business 29+ years, as stated on its own website, read 29 Sept 2026

   Not yet on record: client reviews, vetting.

4. =3

   

   Annex

   Mexican contact centre company running tailored omnichannel customer service and bilingual campaigns for Mexican and foreign firms

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   Why #3 (shared): Office in California · Founded 1997, as stated on its own website, read 28 Sept 2026

   Not yet on record: client reviews, vetting.

5. 5

   

   C3i3 Interactive

   Web Design · SEO · Property

   C3i3 Interactive is a web design and development company in Alameda, California, working with businesses across the San Francisco Bay Area, including San Jose and Oakland.

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   Why #5: Based in Alameda, California · Founded 2002, as stated on its own website, read 28 Sept 2026

   Not yet on record: client reviews, vetting.

6. 6

   

   Genuine Web

   SEO

   Genuine Web is a web design and online marketing company in Bakersfield, California.

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   Why #6: Based in Bakersfield, California, USA · In business 22+ years, as stated on its own website, read 29 Sept 2026

   Not yet on record: client reviews, vetting.

7. 7

   

   Forward Leap Marketing

   Tax · Brainstorming

   Forward Leap Marketing is a lead generation company for tax professionals in the United States.

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   Why #7: Based in Irvine, California, United States · Founded 2015, as stated on its own website, read 29 Sept 2026

   Not yet on record: client reviews, vetting.

8. Also listed, not yet ranked. We hold nothing checkable on these yet that ranks them here: no client review, vetting, award, expert review, or fact stated on their own website (and on a place ranking, where they are based). They follow in order of their TrustList Score. How TrustList ranks · Get vetted, free
9. –

   

   Direct Line

   Call Center · Medical · Property · Also in United States and Nice

   Direct Line - Phone Answering Services provides live telephone answering and call centre cover for businesses in the United States, day and night.

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   On record: Founded 1979, as stated on its own website, read 29 Sept 2026

10. –

    

    GoldenComm

    Business Services · Web Design · Medical · Also in Newport and Orange County

    GoldenComm has built business websites since 1996, with a focus on sites that produce results for the companies that own them.

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    On record: Founded 1996, as stated on its own website, read 28 Sept 2026

11. –

    

    Elite Virtual Assistants

    Virtual Assistant

    Elite Virtual Assistants, also called EVA, provides remote assistants who take on administrative work for busy professionals.

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    On record: In business 20+ years, as stated on its own website, read 29 Sept 2026

12. –

    

    31West

    Also in San Francisco

    31West supplies outsourced IT support and customer service to businesses in the United States and Europe.

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    On record: Based in San Francisco, California, United States

13. –

    

    Answer California

    Business Services · Real Estate · Medical

    Answer California is a call centre and business answering service run from an office in San Diego.

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    On record: Based in San Diego, California, US

14. –

    

    Bright Valley Marketing

    Business Services

    Bright Valley Marketing helps businesses in Sacramento and further afield win more enquiries online.

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    On record: Based in Sacramento, California, United States

15. –

    

    DC3 Medical Billing Service

    Medical Billing · Medical · Insurance

    DC3 Medical Billing Service is a small medical billing business in San Bernardino, California, run by its owner, Rachel, who handles each client's billing personally.

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    On record: Based in San Bernardino, California

16. –

    

    Emerge Marketing Strategies

    Emerge Marketing Strategies is a digital marketing company in Sacramento, California.

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    On record: Based in Sacramento, California

17. –

    

    Girl Friday Associates

    Creative · Also in Sunnyvale and San Jose

    Virtual personal assistant service in Silicon Valley offering administrative and technical support to executives and firms

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    On record: Based in Silicon Valley, California

18. –

    

    Golden West Medical Billing

    Medical Billing · Medical · Insurance

    Golden West Medical Billing, Inc., known as GWMB, handles billing for medical practices from Los Angeles, California.

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    On record: Based in Los Angeles, California, USA

19. –

    

    Griebel Billing

    Insurance · Tax · Security

    Griebel Billing is a small billing practice run by Linda Griebel, who has worked in mental health billing since 1987.

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    On record: Based in California, United States

20. –

    

    HelpLama

    eCommerce · Automation

    HelpLama offers outsourced customer service alongside a helpdesk platform that gathers customer conversations in one place. The company lists an address in Walnut, California.

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    On record: Based in Walnut, California

21. –

    

    HiveMind Studio

    Digital Marketing · SEO · PPC

    HiveMind Studio is a digital marketing agency in San Jose, California.

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    On record: Based in San Jose, California, USA

22. –

    

    Horizon Revenue Solutions

    Horizon Revenue Solutions is a medical billing company based in San Jose, California.

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    On record: Based in San Jose, California, USA

23. –

    

    Information Process Solutions

    Digital Marketing · Responsive · Creative

    Information Process Solutions, also styled IPS USA, is a California agency that combines business process outsourcing with digital marketing.

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    On record: Based in California, USA

24. –

    

    Instinct Marketing

    Sacramento digital marketing agency offering web design, SEO and paid search and social advertising for local businesses

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    On record: Based in Sacramento, California

25. –

    

    Koalified Leads

    DataBase

    Koalified Leads is a business-to-business marketing firm based in Los Angeles. It supplies prospect information and qualified sales leads to vendors selling internationally.

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    On record: Based in Los Angeles, California, USA

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