Serviceable Obtainable Market (SOM)

Serviceable Obtainable Market (SOM) is the slice of demand a company can realistically win in a defined window — usually the next 12 to 36 months — given the reps it has, the regions it sells into, the price it charges, and the competitors already sitting in those accounts. Total Addressable Market is the ocean. Serviceable Addressable Market is the part you can legally fish. SOM is the catch you'll actually land before the quarter closes.

How SOM Is Calculated

There are two paths, and the gap between them is where the lying happens.

Top-down: SOM = SAM × realistic market-share percentage. A company with a $400M SAM and a defensible 5% share is staring at a $20M SOM.

Bottom-up, which boards trust more: SOM = (number of quota-carrying reps × annual quota capacity × expected win rate). This version ties the number to headcount you can actually count, not a share figure you pulled from a McKinsey chart.

SOM Worked Example

A Series A vendor sells HR software to US companies with 200–2,000 employees. The category TAM is $4B. Filtered to that employee band and US-only, SAM lands at $400M. The team runs 12 AEs carrying $1.2M quotas, closing at a 22% win rate against an installed Workday base. Bottom-up SOM: 12 × $1.2M × the pipeline they can actually source ≈ $18–22M of obtainable revenue. Not the $4B on slide three.

When Sales Teams Use SOM

Founders use SOM when fundraising, because a credible obtainable number beats a fantasy TAM in every diligence call that matters. RevOps uses it to set territory designs and headcount plans — you can't capture $20M with six reps. Finance uses it to sanity-check the annual operating plan against capacity rather than ambition. The board uses it to ask the only question that counts: of everything you could sell, how much will you?

Common SOM Gaming Patterns

SOM is the most abused number in the pitch deck, and the abuse follows a script.

The 1% fallacy comes first. "The market is $40 billion — we only need 1% to hit $400M." That sentence has ended more diligence processes than any spreadsheet, because it inverts the math: share is the output of capacity and execution, not an input you assume into existence. Nobody captures 1% of a market by deciding to.

Then there's SAM laundering. A team quietly widens the SAM definition — adds three geographies they have no reps in, includes a customer segment their product doesn't serve — so the same share percentage produces a bigger SOM. The denominator moved; the business didn't.

The third pattern is capacity blindness. A bottom-up SOM that ignores ramp time treats a rep hired in November as a full producer in December. Real obtainable revenue is gated by how fast you can hire, ramp, and generate pipeline — not by how fast you can multiply cells.

What SOM does not tell you: whether the demand exists right now or whether you've just described a market that buys on a five-year cycle. A real SOM survives the question "show me the named accounts and the reps assigned to them." A fake one survives only until someone asks.