How TAM, SAM and SOM differ in a working account list
TAM covers every company that could, in principle, need your category of solution. SAM narrows that down to companies you can serve today by geography, language, deal size, industry and sales model. SOM is not a percentage for a presentation: it is a concrete queue of accounts with a reason to start a conversation and a clear route to a decision-maker.
| Level | Question | Example for an integrator |
|---|---|---|
| TAM | Who could need automation? | All companies with accounting and operational processes |
| SAM | Who can our current team serve? | Russian manufacturers with the required technology stack and budget |
| SOM | Who do we contact in this wave? | Manufacturers hiring analysts or opening a new site |
When one list mixes all three levels, the campaign may look active but its replies are hard to interpret. A rejection from a TAM account does not disprove the offer; that company may simply sit outside your reachable market. To select SOM, define your <a href="/en/glossary/icp/">ICP</a> first, then collect verifiable company details, location, size, business activity and a signal that supports outreach.
How SOM size changes the email and the campaign conclusion
A narrow SOM lets you write from an observable fact. Instead of “We help manufacturers automate operations,” an opening line might refer to a newly opened production site and the accounting issues that often appear when a second operation goes live. That does not guarantee a reply, but it gives the recipient a concrete reason to answer “relevant” or “not for us.”
- Choose one hypothesis: an industry, a decision-maker role and a situation your solution changes.
- Check that the situation can be confirmed through a company profile, public register, vacancy or news item.
- Build a separate account queue and exclude companies without that signal.
- Review replies by segment before expanding the scope.
For example, an equipment supplier may place operating manufacturers, design firms and dealers in the same first wave. Replies saying “we do not operate equipment” point to a list problem, not necessarily a copy problem. Separating those groups makes the hypothesis testable before scale; see <a href="/en/cases/test-b2b-icp/">how to test a B2B ICP before hiring sales</a>.
Where TAM, SAM and SOM will not give you a sales plan
This model is not a revenue forecast when you do not know the sales cycle, meeting-to-contract conversion or the real capacity of your sales team. It also breaks down when the offer is too broad: “marketing for business” cannot be turned honestly into a reachable market without an industry, deal size and a defined customer outcome.
- Do not start with TAM if you do not yet have one clear product and buyer.
- Do not transfer SOM from another region without checking local demand.
- Do not scale a list after a few replies; first read the reasons for interest and refusal.
- Do not mistake a set of email addresses for a reachable market without checking the companies and contacts.
Once the inputs are clear, market sizing becomes a campaign brief: which accounts to find, which to exclude and what question to put in the first touch. OT9 can turn that brief into a focused list and campaign through <a href="/en/services/full-service-outreach/">full-service B2B outreach for Russia and CIS</a>.