When to send
| Type of appointment | When | Channel |
|---|---|---|
| Booked a few days ahead | The day before | Text message |
| Booked a week or more ahead | A week before and the day before | Email and text message |
| Needs preparation (e.g. fasting, documents) | Two days before, with instructions | Email and text message |
The time of day matters too: a reminder sent in the morning or early afternoon leaves time to cancel and to invite someone else to the freed slot.
What to write
Short and specific: who, when, where and what to do if the date doesn't suit. A sender name instead of a random number makes the text look trustworthy.
Lipowa Clinic: a reminder of your appointment tomorrow at 14:30, 5 Lipowa St. Confirm or cancel: https://clinic.example/a/8KX2
A text message containing characters outside the basic GSM alphabet (Polish ą, ę, ł and others) is encoded differently, and one message then fits 70 characters instead of 160. A longer reminder arrives as several joined messages, and each one is paid for. Most SMS gateways can replace such characters automatically.
How to build it
- The source of appointments
A booking system or calendar from which tomorrow's appointments can be fetched, ideally through an API.
- An automation once a day
It picks the appointments for tomorrow (and in a week) and prepares the messages.
- Sending
An SMS gateway with a sender name and a mail server with SPF, DKIM and DMARC set up correctly, so emails don't land in spam.
- A link to confirm or cancel
With a one-time code, without signing in. The client clicks and it's done.
- The freed slot goes back
A cancellation frees the slot in the calendar and can notify people on the waiting list.
All of it can be done in an automation tool such as n8n or Make, or as a small program. Many ready-made booking systems have reminders built in, and then it's enough to switch them on and polish the wording.
What to avoid
- Advertising and offers in the reminder. Then the message stops being information about the service and needs marketing consent.
- Sensitive details in the text, for example the name of a treatment or the doctor's specialty. Someone else may read the message.
- Sending at night or in the wrong time zone. An automation running on universal time (UTC) will send the message an hour too early or too late after the clocks change.
- Emails without SPF, DKIM and DMARC. They'll land in spam, and the client will think nobody reminded them.
How to measure the effect
Write down how many appointments were lost without cancellation in the month before the rollout and compare with the month after. I don't give a specific number here, because it depends on the industry, the clients and how easy it is to cancel. The cancel link usually makes the biggest difference, because a freed slot can be taken by someone else.
Terms from this guide
- No-show
An appointment the client didn't attend and didn't cancel. Reminders with a cancel link reduce such cases.
Questions and answers
Do I need the client's consent for reminders?
A reminder about a booked appointment is part of the service the client ordered, so marketing consent isn't needed as long as the message contains no advertising. The phone number and what you use it for still have to be described in the privacy policy.
Text message or email?
Text messages are usually read faster than emails and don't get lost in spam. Email fits more details: directions, preparation, documents. For important appointments, both work best.
Can this be done in a ready-made booking system?
Yes, many ready-made systems have reminders built in. Then it's worth just polishing the wording, the sending time and the cancel link.
Sources and documentation
- Gmail: email sender guidelinessupport.google.com
- Regulation (EU) 2016/679 (GDPR): the full text on EUR-Lexeur-lex.europa.eu