A reminder sent at the wrong moment is not a smaller version of a good reminder. It does nothing at all, and it costs you the goodwill of having messaged someone for no reason.
The purpose of a reminder is not to inform. The client already knows they booked. The purpose is to arrive at a moment when they can still act on it: move the appointment, cancel it in time for you to refill the slot, or realise they need to rearrange something else.
Which means the right question is not "when will they read this" but "when can they still do something about it".
The three moments that matter
FindSlot sends client reminders at seven days, twenty-four hours, and one hour before the appointment. Those are three different jobs, not three attempts at the same one.
Seven days out — the planning window
This is the only reminder that reaches the client while they still have real flexibility. A week ahead, someone can move a work meeting, arrange childcare, or decide the appointment no longer fits and cancel it cleanly.
It is also the reminder most businesses skip, because a week feels too early to be useful. It is the one that recovers the slots you can actually resell.
Twenty-four hours out — the decision point
The workhorse. At a day's notice the appointment is real enough to plan around and still far enough away to move. This is where most cancellations that were going to happen anyway get surfaced, which is exactly what you want: a cancellation at 24 hours is a slot you can still fill.
It is also the point at which most cancellation policies take effect, so the reminder and the policy should say the same thing. If your policy asks for 24 hours' notice, a reminder arriving at 24 hours is the last honest chance to give it.
One hour out — the logistics nudge
This one is not about whether they attend. It is about whether they arrive on time and in the right place. By this point a cancellation is a lost slot regardless, so the job is different: reduce lateness, not absence.
Keep it short. Time, place, and nothing else.
Why not just send one
A single reminder has to choose between the three jobs above and will do at most one of them. Send it early and it is forgotten by the day itself. Send it late and anyone who needed to rearrange no longer can, so the message arrives as an announcement rather than an option.
The sequence matters more than any individual message. Someone who cannot attend will usually act on the first reminder that reaches them while acting is still possible.
What the timing cannot fix
Timing only works if the message gives the client something to do. A reminder that states a time and nothing else puts the burden back on them: to find your number, to call during opening hours, to have that conversation. Most people will not, and the appointment quietly becomes a no-show.
Every FindSlot reminder includes a link to the appointment itself, so rescheduling takes a few taps instead of a phone call. That is the part that converts a well-timed reminder into a recovered slot. Wording that makes this obvious is covered in appointment reminder templates.
Channels
Reminders go out by email and, where the business has it enabled, by SMS as well. SMS is read sooner, which matters most for the one-hour message; email carries more detail comfortably, which suits the seven-day one.
The channel matters less than most articles suggest. A well-timed email beats a badly timed text, and neither rescues a message the client cannot act on.
Reminder timing FAQ
Is 24 hours enough notice?
For refilling a slot, usually yes. For the client rearranging their day, often not — which is why the seven-day reminder exists alongside it.
Do multiple reminders annoy people?
Rarely, when each has a distinct purpose and none repeats the last. What irritates people is the same message three times.
Should long appointments be reminded differently?
They benefit most from the earliest reminder, because they are the hardest to refill at short notice and the most disruptive to lose.
What about appointments booked the same day?
Earlier reminders simply do not apply. The one-hour message does the whole job.
For the wider picture, see reducing appointment no-shows. If clients are missing appointments despite good reminders, a written no-show policy addresses the part reminders cannot.
