“My calendars are connected, the occupancy matches — and I still send every guest the check-in link by hand.” That sentence sums up exactly where iCal ends. Here's what iCal can do, where it falls short, and when it pays to take the next step.

What iCal can do

Transfer booked dates between calendars. Airbnb knows that Booking sold the weekend and blocks it. It's free and takes a few minutes to set up on each platform: on Airbnb under Availability → Connect calendars, on Booking under Rates & Availability → Sync calendars. For one apartment on two platforms, it's a sensible start.

What iCal can't do

• Real time. Airbnb imports every 3 hours, Booking every 2 hours. Booking itself says the sync isn't real-time. In peak season two guests can end up with the same dates — and the double booking is yours to sort out.
• Name, e-mail, phone, price, number of guests. iCal carries none of that. Dates and a few technical fields. Without the guest's identity you have no one to send the check-in to and nothing to report to UbyPort (the Foreign Police reporting system).
• The last channel outside the system. A booking by phone, a friend, an inquiry portal — as long as anything goes around the connected calendars, the risk remains.

Two practical traps: mixing up export and import (the calendar looks like it's working and transfers nothing), and posting the calendar link to the cleaning team's group chat — it carries guests' personal data and isn't password-protected.

When iCal stops being enough

The moment you want to automate guest check-in. The check-in link, reporting to the police, the evidenční kniha (guest register), pre-arrival messages — all of it needs to know who's coming, how many of them there are, and how to reach them. iCal can't do that and never will.

The solution is an API connection: a channel manager or PMS (property management system) that is connected to the platforms as a “connectivity provider” and transfers complete reservations, including the guest and the price, instantly.

What it costs and what to watch out for

Prices range from roughly €15 a month (Beds24) to €50–100 for larger systems; the Czech Previo starts at CZK 550 a month excluding DPH (Czech VAT) for one room and one portal. What to watch out for:

• Not every plan includes API access. Neither Hospitable Essentials nor Hostex Basic has API access; without a paid plan you can't set up the connection.
• Keys expire. The Hospitable token after a year, the Beds24 refresh token after 30 days of non-use, and Smoobu is switching off old keys on 25 September 2026. The connection needs renewing every so often.
• Permissions. With Beds24 and Hostex, minimal permissions will cut off prices and guest personal data — exactly what you're setting up the connection for — and you can't extend them after the fact.
• Booking with a connectivity provider no longer has iCal. A property connected via API doesn't have the Sync calendars feature in the extranet. You can't have both.

When it doesn't pay off yet

One apartment, two platforms, a few dozen bookings a year, and you don't mind checking guests in by hand: iCal is enough, and you send the check-in link yourself. Once you have two apartments, or you want the reporting and the registers to run without you, the math changes: an hour a week of manual copying costs more than €15 a month.

How I do it

Reservations come in from the platforms through a channel manager, complete with the guest and the price. The reservation triggers the check-in invitation, the check-in triggers the report and the register entries. I've kept iCal only where there's nothing else: for Czech cottage-rental portals that don't have an API. Even there, though, I add the guest to the reservation by hand, because without them I have nothing to report.