Top Online Advertising Agencies in California

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Online Advertising United States California

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Top Featured Online Advertising Agencies

Fellow Partners
5
(8 reviews)
Your partner for commercial success.
Recommended
Top awarded
Welcome to Fellow Partners. We're an award-winning international brand and marketing agency helping businesses create commercial momentum through brand strategy, identity and integrated marketing campaigns. At Fellow, we believe great brands should do more than look good—they should drive growth. We combine strategic thinking with creative excellence to build brands, launch campaigns and deliver marketing that helps businesses win customers, increase sales and strengthen market position. Working as an extension of your team, we provide strategic and creative expertise across every stage of the customer journey, including: • Brand Strategy & Positioning • Brand Identity & Visual Design • Packaging Design • Brand Messaging • Copywriting • Marketing Strategy & Planning • Creative Campaign Development • Content Marketing & Creative Production • Account Based Marketing • Digital Marketing Campaigns & Websites • Media Planning & Buying • International Marketing & Transcreation • Campaign Reporting & Performance Analysis Whether you're launching a new brand, repositioning an existing one, or looking to generate more leads and sales, we create connected brand and marketing programmes that deliver real commercial impact. Our experienced team works across both B2B and B2C sectors, supporting clients throughout the UK , Europe , the US and wider international markets. By combining global strategic thinking with local market insight , we create brands and campaigns that resonate wherever your business operates. As an agile, senior-led agency, we integrate seamlessly with in-house teams or provide a complete outsourced brand and marketing solution. We focus on delivering work that is accountable, measurable and aligned to your commercial objectives. Visit our website and contact us to learn more about Fellow Partners and discover how we can help your business build a stronger brand and accelerate growth . www.fellow.partners
31 works in Online Advertising
Located in London, United Kingdom
From €3,000 for Online Advertising
Worked in Software & Computer Services (+11)
Speaks English, German(+1)
11-50 members
Rex Automaton
(0 review)
We connect the software your business already runs and add AI where it saves real time.
Rex Automaton is an automation and AI studio in Vancouver and Edmonton, working with businesses across North America. Most of our work starts the same way. A company runs on an industry platform that was never built to talk to its other tools, and people copy data between them by hand. We connect those systems through their APIs, add AI where it pays for itself, and keep it running after launch. Recent work: - A call transcription pipeline for a 40 trader commodity firm. More than 39,000 calls written into their database with zero errors, all on their own hardware. - An AI voice agent that calls and books leads for a real estate brokerage. - AppFolio reporting pipelines that turn property data into monthly investor reports. - Document extraction that files receipts, invoices and bank statements into the ledger for an accounting firm. We scope in plain language and quote a fixed price before anything is built. Zapier Silver Solution Partner.
Looking for work in Online Advertising
Located in Vancouver, Canada
From €1,000 for Online Advertising
Worked in Home Services (+5)
Speaks English
1-10 members
Sellucent
5
(6 reviews)
Your Amazon Growth, Decoded - Amazon PPC & Optimisation for UK + international brands
Highly recommended
Sellucent is a London-based Amazon growth consultancy built by former sellers who got tired of watching strong brands leave money on the table. We combine advanced AI analytics with hands-on expertise to turn your Amazon data into clear, actionable strategies that deliver measurable results.Whether you’re launching your first products or scaling an established brand, we focus on what actually moves the needle: lower ACoS, higher ROAS, improved conversion rates, and sustainable, profitable growth across the UK, EU, and international marketplaces. Core services include: AI-powered precision PPC management and bid optimisation Amazon DSP and full-funnel advertising Listing optimisation, keyword research & A+ Content Creative development and brand storytelling Inventory planning, account strategy, and brand protection Every recommendation is data-backed. We operate with radical transparency — you see exactly what we do, why we do it, and how it ties to revenue outcomes. No vanity metrics, no black-box reporting. Our results speak for themselves: clients have achieved 180%+ revenue growth in months, dramatic ACoS reductions (e.g. 42% → 18%), and conversion rate lifts from low single digits to 5%+. We’ve managed hundreds of millions in Amazon revenue across thousands of brands.Sellucent is the agency we wished existed when we were sellers ourselves — one obsessed with performance, partnership, and long-term growth. We only win when you win.
4 works in Online Advertising
Located in London, United Kingdom
From €3,000 for Online Advertising
Worked in Beauty (+3)
Speaks English
11-50 members

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