What it means
When planning a business or launching a new product, it is easy to get carried away by the sheer size of a global market. However, stating that you want to capture one percent of the global coffee market is rarely helpful for day-to-day operations.
SOM brings your strategy down to earth. It represents the actual number of customers you can reach, serve, and win over given your current team size, marketing budget, and distribution channels.
Business leaders and founders use SOM to set realistic sales targets, allocate marketing budgets effectively, and convince investors that their growth projections are grounded in reality rather than wishful thinking. By focusing on this specific subset of customers, you avoid spreading your resources too thin and build a strong foundation for future expansion.
Your SOM shrinks the wider market down to a manageable battlefield where you can actually win.
In practice
Real-world examples.
Example
A local gourmet bakery in Manchester calculates its SOM by looking at coffee lovers living within a two-mile radius who regularly buy artisan bread, resulting in a target of 3,500 regular local customers.
Example
A regional commercial cleaning firm targeting small office buildings in Leeds defines its SOM as the 120 offices currently dissatisfied with their current provider that fit the firm's exact cleaning capacity.
Example
A boutique software agency focusing on mobile apps for independent UK craft brewers estimates its SOM at 45 craft breweries that have the necessary budget and are actively seeking digital upgrades this year.
Think of it
“Imagine the total market is all the fish in the ocean. Your serviceable market is the fish in your specific region. Your SOM is the fish you can actually catch with your current fishing rod and boat.
Formula
Calculation
SOM = Serviceable Available Market (SAM) multiplied by your expected Market Share percentage.
Example: If your SAM is 50,000 potential local customers who can realistically buy your service, and you realistically expect to capture 10 percent of them in your first year due to competition:
50,000 x 0.10 = 5,000 customers.
If each customer spends an average of 100 pounds per year, your revenue SOM is 500,000 pounds.Case study
Seen in the real world.
GreenClean, a fictional provider of eco-friendly office supplies based in Bristol, wanted to pitch for expansion funding. Initially, the founders looked at the entire UK office supplies market, worth two billion pounds, and claimed they would capture five percent of it. Their financial advisor explained that this was unrealistic for a small regional team. They narrowed their focus to create a proper market breakdown. First, they looked at the South West of England, giving them a Serviceable Available Market of forty million pounds. Next, factoring in their current fleet of two delivery vans and a marketing budget of twenty thousand pounds, they calculated their Serviceable Obtainable Market at two million pounds, representing the offices they could genuinely service within a forty-mile radius. Presenting this realistic two million pound SOM to investors showed maturity and deep operational understanding, securing the funding needed to buy a third van and expand their team.
Watch out
Common mistakes.
- Assuming you can capture 100 percent of your target market without facing competition.
- Confusing total global demand with the actual customers you have the resources to reach.
- Failing to update your SOM as your budget, team size, and geographical reach expand.
Questions
People also ask.
How often should I recalculate my SOM?
You should review your SOM annually, or whenever you secure new funding, expand your team, or change your pricing and distribution strategy.
Is SOM the same as TAM?
No. TAM is your Total Addressable Market, representing total global demand. SOM is a much smaller, realistic slice of that market you can actually capture right now.
Why do investors care about SOM?
Investors look at SOM to judge whether your financial forecasts are realistic and whether you understand your operational limits.
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