Why Calendly has no waitlist, and what people do instead

The request is almost always the same, and it is smaller than it sounds. Nobody is asking Calendly to rebuild scheduling. They are asking for this:

• Somebody wants a session, nothing is free for three weeks.
• They should be able to say “tell me if something opens” instead of going away.
• When something does open, they should hear about it while it is still open.

That is it. The people asking are coaches, tutors, personal trainers, massage therapists, small studios: calendars where a free hour is money and there is a real queue of people who want it.

Calendly has not said. What can be observed is that a waitlist is an odd fit for what Calendly is. Calendly is a very good answer to “when are you free”, and it is built to answer that question and get out of the way. A waitlist is the opposite shape: it keeps hold of people, remembers what each of them wanted, and acts on their behalf hours or days later, when nobody is looking at a screen.

That is a different kind of product living inside a scheduler, and it is reasonable to guess the feature keeps losing to work that serves the much larger group of Calendly users whose calendars are not full.

On 3 November 2026 Calendly opened its booking and cancellation API to every plan, Free included. That is not a waitlist, but it matters: until then, anything built on cancellations needed the host to be on a paid Calendly plan, because webhooks were a paid feature. Now a tool can listen for a cancellation and create a booking on any account.

In other words, the thing Calendly did not build became buildable by anybody, on any Calendly plan. That is most of why there are suddenly tools for this.

Reading through the threads, the answers land in three piles.

• A note and good intentions. Most common. A list in a notes app, and a round of messages when something opens. It works until it is you, between sessions, on a phone.
• A Zapier or n8n build. Catch the cancellation webhook, email the list a booking link. This is a real answer and plenty of people run it. What it produces is a broadcast: everybody gets the link, everybody races, and the slot goes to whoever was holding their phone rather than to whoever has been waiting.
• Leaving Calendly. A handful move to a scheduler with a waitlist built in, and the rest price it out and stay, because changing scheduler means changing every link you have ever given anybody.

If you are going to solve this yourself, the webhook is the easy half. The half that decides whether your clients like the result is what happens between the cancellation and the booking.

A single booking link emailed to everybody has four problems, and they are the same four every time: it reaches people who cannot make that time, it rewards whoever refreshes fastest rather than whoever has waited longest, two people can open it in the same second and both believe they have it, and it can lead to a slot that a member of the public took while the email was in flight.

What Slotghost does: Everyone who joins says which days and times they can do, so a Tuesday afternoon slot is only ever offered to people who said Tuesday afternoons. Offers go out a few at a time with a deadline, in the order people joined, and nobody further down is offered it until that time is up. Claiming books the slot in one press, and the slot is locked while that happens, so two people claiming at once get exactly one booking between them.

It is possible, and worth saying plainly rather than pretending otherwise. The likely shape is a notify list: everybody told, everybody races, which is the broadcast again with better delivery.

The parts that take real work are the queue, the lock, seats on group events, and keeping a record of the days and times people asked for and could not get. That last one is the one worth having for its own sake, because it is the only way you ever find out that eleven people wanted Tuesday evenings.