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Serotonin is a performance marketing agency for brands that want to perform better, faster. Founded by Dom Carter & Clair Heaviside; with over a decades of experience scaling brands across the UK, Europe and the US. We don’t hide behind jargon, vanity metrics or bloated presentations. Instead, we bring clarity, pace, and commercial focus to every stage of the funnel. From forecasting and strategy through to paid media, performance creative and CRO, we help brands get to where they want to go—faster. Our team blends deep platform expertise in Meta, Google, TikTok and Amazon with a creative mindset built for modern attention spans. We care about customer journeys as much as we care about click-through rates. And we know how to turn performance data into direction that brands can actually act on. We’ve scaled fashion labels from £5k to £100k/month, launched global fitness brands into new markets, and helped heritage names modernise their approach to digital. Whether you’re building from scratch or stuck at a revenue plateau, Serotonin brings momentum. We work best with founders, marketers and CMOs who value straight-talking partnership and measurable results. The ones who want fewer meetings and more movement. This isn’t an agency that adds noise. It’s one that brings signal. Serotonin: the performance partner for ambitious brands. Read more