The honest, mechanism-based answer
Robert Cialdini's well-established research on scarcity describes a real psychological mechanism: reduced access to something tends to increase its perceived value. It's plausible that sustained silence increases how noticeable your absence becomes to your ex. That's a real mechanism, not a guarantee of a specific outcome.
Why this shouldn't be the reason you do it
Even where the mechanism is real, you don't control how a specific person responds to it, on what timeline, or whether they act on it at all. Building a 40-day plan around a hoped-for reaction outside your control sets you up to measure your own progress by someone else's behavior — which is a worse plan than measuring it by your own.
Build the plan around what you can actually control.
No Contact 40 Days tracks the part that's actually yours — your streak, your reasons, your recovery.
Get the app on the App StoreCommon questions
So is no contact pointless if I want them back?
Not pointless — it gives you clarity and space either way — but it shouldn't be the only reason you're doing it, since the outcome you're hoping for is outside your control.
How long before an ex starts to miss you?
There's no reliable timeline, and chasing a specific number tends to create more anxiety than clarity.
No Contact 40 Days is a personal-motivation and self-improvement tool. It is not therapy or medical or mental-health advice, and it is not a substitute for professional care. If you're struggling, please reach out to a qualified professional or a local support line.