Appointment reminders: Telegram, SMS or email

Which channel to use, how far ahead to send, and how a reminder differs from a notification

A reminder is a message on a schedule tied to the appointment time. It fires at the right moment even if nothing about the appointment changed. A notification is a different thing: it reacts to an event, meaning an appointment being created, moved or cancelled. Confusing the two is behind most setups that "do not work".

Reminder or notification

	Reminder	Notification
What triggers it	The calendar	An event on the appointment
Example	"See you tomorrow at 15:00"	"Your appointment has been moved"
Fires when nothing changed	Yes	No
Where it is configured	Messaging, appointment reminders	Messaging, appointment notifications

Both are configured for the current branch, so a chain has to set them up in each one.

Which channel to use

Channel	When it fits	What to bear in mind
Telegram	The primary channel where your clients use it	Cheapest, but the client has to subscribe to the bot first
SMS	Always arrives, no app and no internet needed	Dearest per message, worth signing with your company name
Email	Long messages, confirmations, receipts, documents	Cheap, but not read immediately

The working combination for most companies is Telegram as the primary channel, SMS as the fallback for anyone not subscribed, and email for documents. Credit prices are published on the pricing page; the order is that Telegram is the cheapest and SMS the the most expensive, which is exactly why the bot subscription is worth offering the client straight away.

How to connect Telegram

Three reminder types

The type decides what the send time is measured against:

Type	When it is sent
A set time before	A given number of minutes, hours or days before the appointment starts
At a fixed time of day	At a chosen hour, offset relative to the day of the visit
Remind after	A given interval after the visit

The second type solves a problem people rarely think about. A "12 hours before" reminder for a 09:00 appointment arrives at 21:00 the night before; for an 08:00 appointment, at 20:00. A fixed time sends everyone theirs at 19:00 regardless of their hour, so nobody is messaged in the middle of the night.

How many, and when

The sensible minimum is two:

A day before. It gives the client time to cancel or move while you can still sell that slot to somebody else. This is where a fixed time of day works better.
Two or three hours before. It catches the ones who remember the day but not the hour.

A third, a week ahead, only earns its place where people book far in advance: healthcare, rentals, events.

The Remind-after reminder is a separate tool and it is not about no-shows: it asks for a review, offers a repeat visit, or reminds the client about aftercare.

Configuring reminders in full

Why a message did not arrive

Check in this order, sorted by how often each is the answer:

The client is not subscribed to the bot and the reminder is set to Telegram only.
The reminder was created in a different branch.
Credits have run out.
The number is stored in a format the provider will not accept.
The reminder time had already passed when the appointment was created. A same-day booking gets no "day before" reminder.

The fifth is the most common "fault" that is not a fault.