SAM (serviceable addressable market) is the revenue opportunity available to your product given current capabilities, geography, regulation, and go-to-market reach.

How it works

Market sizing stack:

• TAM: Total theoretical demand if everyone bought a solution in the category globally.
• SAM: Segment you can serve with today’s product — e.g., U.S. mid-market healthcare clinics, not all hospitals worldwide.
• SOM: Share you can realistically win near-term given competition and capacity.

Bottom-up SAM example: 50,000 target companies × $20K ACV = $1B SAM. Top-down SAM might filter industry reports to your niche.

Credible decks show assumptions: why vertical limits exist, expansion path from SAM to broader TAM, and bottom-up TAM cross-check.

Why it matters

• Founders: SAM focuses sales ICP and product roadmap — chasing full TAM early dilutes effort.
• Investors: SAM must support venture-scale outcomes; tiny SAM caps return potential even with great execution.

Common mistake

Equating SAM with TAM by citing a giant industry report without filtering to buyers you can actually reach this year with your SKU and price.

Related ideas

See also TAM, bottom-up TAM, beachhead market, and ICP.