Sponsor a niche B2B newsletter read by your exact ICP. CAC often 40-60% lower than paid search for tight niches.
Identify newsletters with 2,000-15,000 subscribers in your exact ICP (DevOps engineers, retail CFOs, solo law firm partners, etc). Negotiate a "sponsor segment" — typically $500-$3k per send. Write the sponsor copy like an editorial recommendation, not an ad. Track with a unique UTM and landing page. Run 3-4 sends before evaluating; newsletter performance compounds as trust builds. Works best for products with a clear ICP and a self-serve or short sales cycle.