Slack
How Slack grew with freemium + word of mouth
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Brand awareness
Lower
Cost per customer
Compounding
Word-of-mouth
The challenge
Slack operated in a crowded saas market where standard advertising was expensive and easy to ignore.
The unique move
A generous free tier turned users into evangelists and fuelled viral B2B growth.
How it grew them
The move gave Slack outsized reach for the budget, compounding word-of-mouth and turning early attention into sustained sales growth.
What you can borrow
You don't need the biggest budget — one bold, well-targeted idea like freemium + word of mouth can outperform expensive, generic campaigns.