Upgrade prompts work at the limit, not before
A random "Upgrade to Pro!" banner in the dashboard is noise. The user isn't thinking about upgrading. They're trying to do their work. The prompt is an interruption with no context.
The same prompt shown when the user tries to do something their plan doesn't allow is a solution. "You've used 95% of your storage. Upgrade to Pro for unlimited storage." Now the upgrade solves a problem they're experiencing right now.
The timing difference produces roughly 5x the conversion rate. Not because the offer changed. Because the motivation existed at one moment and not the other. People don't upgrade because upgrading sounds nice. They upgrade because they need something they can't currently do.
Map your plan limits and trigger upgrade prompts at 80-90% usage. Not at the hard wall. Slightly before it, when the user can see the limit approaching but hasn't hit it yet. This gives them time to decide without the frustration of being blocked.
Identify your most common plan limit. Add a contextual upgrade prompt when users reach 80% of that limit. Compare upgrade rate vs your current prompt placement.
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