What’s the best way to size the market without double counting segments?

[Gary.M]

I’m trying to size up the total addressable market for a niche B2B software tool, but I’m stuck on how to accurately segment the small business sector without double-counting potential clients or missing hidden segments. My initial market sizing feels off because the available industry reports use such broad NAICS codes.

[Joseph.M]

Yeah, I went through the same thing last quarter. I started with ICP definitions but kept running into overlaps. We split into two layers: core buyers (budget holders) and influencers (indirect buyers like ops managers). Then I cross-checked against job titles and company size so we didn’t count the same brand twice when a single company shows up in multiple lists.

[Luna.R]

I tried pulling data from broad NAICS buckets and then tried to prune by product fit signals we actually see in usage logs. We found hidden segments like bookkeeping firms and outsourced IT vendors who resell our tool, which weren’t obvious in the codes. We had double-counts when a firm shows up in two NAICS buckets and two reseller programs.

[AdamL]

Maybe the problem isn't segmentation at all. It might be that the tool doesn't align with what small shops actually need, so counting more won't help. I started calling a few prospects just to sanity check, and several were unsure whether our tool would solve their primary pain, even though the data said they should be in scope.

[Alexander5]

I did a bottom-up rough TAM by estimating the number of potential users per target company and multiplying by typical deal size, but the numbers felt off because we couldn't pin down who actually buys or who makes the decision in practice. We paused and considered a pilot to validate who signs the checks, rather than chasing a precise market size.