TAM / SAM / SOM

TAM, SAM and SOM are three levels of market size assessment. TAM (Total Addressable Market) - the entire market, if the product were bought by everyone to whom it is in principle suitable. SAM (Serviceable Available Market) is the part that you can actually reach by geography and channels. SOM (Serviceable Obtainable Market) is a share that can actually be taken, taking into account competitors and budget.

These three letters are needed to keep goals and budget on the ground. “We want 100,000 customers” sounds good until it turns out that the entire SAM consists of 40,000 companies. TAM/SAM/SOM translates ambition into verifiable numbers.

There is no need to count to the penny - you need an order of magnitude. I usually collect estimates from open data: industry statistics, the number of companies in the desired segment, average bill. The goal is not accuracy, but to understand: the market generally accommodates the growth plan or we will hit the ceiling in a year.