Sync Booking, Airbnb and VRBO with iCal for Spanish Rentals

If you manage a tourist accommodation, you probably know the pain.

The same night booked on Booking. Another on Airbnb. Another direct through WhatsApp. And the constant fear of a double booking.

That fear has a concrete cause: every portal keeps its own calendar and none of them knows what just happened next door. Working faster doesn’t fix it, because the problem isn’t your typing speed, it’s that your availability lives in four places at once. The standard the industry has used for decades to pull it together is called iCal.

Below you’ll find what iCal is, where to find the link on each major portal (Booking.com, Airbnb, VRBO, Expedia, Tripadvisor, Google Calendar, Holidu, Rentalia), and how to connect it to your guest registration software so each reservation generates the digital check-in on its own.

What an iCal is

iCal (.ics format, RFC 5545) is an open standard for exchanging calendar information¹. Each calendar event is described with fields: start date, end date, title, description, and a unique identifier.

Applied to the accommodation world, an iCal is a public URL (something like https://ical.booking.com/v1/export?token=...) that returns a text file with all the reservations for a property. Any software capable of reading iCal can import those reservations and keep them up to date.

Advantages of syncing by iCal

It’s an open standard, so it doesn’t depend on any commercial agreement between portals. Google Calendar, Outlook, Apple Calendar, and almost any PMS read it. Once configured, the software queries the URL every so often and detects changes by itself. And you don’t need an API or fiddly keys: a URL is enough.

iCal limitations: incomplete data, delay and read-only

The iCal tells you there’s a reservation between two dates, but it doesn’t always include the guest’s name, email, or phone. For full data you still need the source portal or an API integration.

Portals don’t publish changes instantly either, so delays of 5–30 minutes are common. And in most cases iCal is read-only, so blocking dates on the portal means writing back, which is already a two-way sync.

What data an iCal includes and what it does not

A typical OTA portal iCal includes:

• Check-in date and check-out date (DTSTART and DTEND, the fields RFC 5545 actually defines).
• Unique reservation identifier (UID).
• Source (Booking, Airbnb, VRBO, etc.).
• Status (confirmed, cancelled).
• In some cases, guest name (partial or full) and reservation code.

What it usually does not carry: DNI, passport, date of birth, address. So it doesn’t replace check-in. It just flags that there’s a stay. You still collect the guest’s personal data for the guest report exactly as before; the difference is that the reservation already exists in your system and all that’s left is to send the link.

Where to find the iCal URL on each portal

Booking.com iCal URL: where to find it

1. Log in to the Booking Extranet with your property owner account.
2. Go to Rates and availability → Calendar sync (the exact name may vary by version).
3. Click “Export calendar”.
4. Copy the iCal URL it shows you.

Booking exports an iCal per accommodation and per room type. If you have several rooms or apartments, each one has its own URL.

How to find the iCal URL on Airbnb host calendar

1. Log in to your Airbnb host account.
2. Go to Listings → select the accommodation → Calendar → Availability.
3. In the “Sync calendars” section, click “Export calendar”.
4. Copy the URL Airbnb provides.

Each Airbnb listing has its own iCal. If you manage several listings of the same flat, each has its own URL.

VRBO iCal export link for property managers

1. Log in to the VRBO Owner Dashboard and pick the listing.
2. Select Calendar and, under Settings, open the Availability tab.
3. Under “Calendar sync”, select “Connect calendars” and then “Export calendar”.
4. Select “Copy URL”.

VRBO gives you one export URL per property, and it is the same link wherever you plug it in: its help centre tells you to copy that URL and then follow the instructions of the external calendar or booking website you are importing it into². Expedia Traveler Connection has a similar flow through its partner dashboard.

Google Calendar

If you handle direct reservations or manual blocks in a Google Calendar, you can also expose it as iCal:

1. Open Google Calendar.
2. In the calendar list on the left, click the three dots on the calendar you want to expose → “Settings and sharing”.
3. Scroll down to “Secret address in iCal format” and copy the URL.

Holidu

1. Sign in to the Holidu Owner Portal.
2. Select the property.
3. Under Calendar → iCal sync, copy the export URL.

Holidu publishes one URL per listing. If you manage several, there’s one per listing.

Expedia, Tripadvisor Rentals and Rentalia: where the iCal feed is

All three expose the calendar from the host dashboard, in a section called “Sync”, “Export calendar”, “Calendar feed” or “iCal feed” depending on the portal. The flow is the familiar one: open the listing, open the calendar, copy the export URL.

If you also list on some other platform (HomeAway, SpainHolidays and the like), look for that same section: as long as the URL returns an .ics, any iCal reader understands it.

How to connect an iCal to RegistroViajero

Once you have the iCal URLs for each portal, the flow in RegistroViajero is straightforward:

1. Dashboard → Accommodations → select the property → “Calendars” tab.
2. Click “Add iCal source”.
3. Paste the URL, choose the source, and save. The list is closed, with eight options: Booking.com, Airbnb, VRBO, Expedia, Tripadvisor, Google Calendar, Holidu, and Rentalia.
4. The system runs an immediate first sync and then keeps syncing automatically every 15 minutes.

From that point on, each new iCal event turns into a reservation in your dashboard, with check-in and check-out dates pre-filled. If you turn on the auto check-in link, the system generates the unique link for the guest as soon as the reservation appears, ready for you to forward or to go out by email automatically.

How often does the Airbnb iCal update bookings?

The most common question. Short answer: it depends on the portal.

• Airbnb publishes iCal changes with a typical delay of 2–4 hours. Sometimes more.
• Booking sits between 30 minutes and 2 hours.
• VRBO runs in similar ranges to Booking.
• Google Calendar updates almost instantly, but the client consuming the iCal has its own polling cadence.

RegistroViajero polls iCal sources every 15 minutes by default. In practice, a reservation takes the portal’s publishing delay plus the next polling cycle to land in your dashboard. If you need it sooner, force a manual sync from the dashboard.

iCal sync cancellations on Airbnb, Booking, and VRBO

When a reservation is cancelled on the source portal, the iCal stops including it. The system detects the difference.

If you have auto-cancellation enabled, the reservation in RegistroViajero is marked as cancelled. If it had already been sent to the Ministry, the corresponding cancellation notice is submitted automatically.

One caveat. Some portals don’t drop the iCal entry immediately, and others serve the file from a cache, so the same URL can keep returning the previous version for a while. Between the two, a cancellation can take 1–2 sync cycles to propagate. If a cancelled reservation still shows up, force a manual sync and check again 30 minutes later.

Best practices for syncing multiple portals

Connecting a single iCal is rarely enough. You’ll usually want to connect every portal where you publish the same accommodation. That’s where the nuances start.

1. One iCal URL per portal, not per room

If you have an entire apartment on Booking and the same apartment on Airbnb, you need both URLs connected to the same property in your software. That way the internal calendar reflects reservations from both portals.

2. Block dates on Booking and Airbnb at once

An incoming Booking reservation, in principle, doesn’t automatically block availability on Airbnb. For that you need a two-way sync:

• With bidirectional iCal (each portal consumes the other’s iCal). Works, but with a delay: a Booking reservation may take 15–30 minutes to show up as a block on Airbnb.
• With a channel manager (direct API integration). Faster and more reliable, but also more expensive and more complex.

For medium volumes, bidirectional iCal between portal pairs is usually enough. At high volumes, go with a channel manager.

3. Use the same accommodation name on every portal

If the same apartment has different names on each portal (“Centro 1A”, “Downtown Apartment 1A”, “Apt 1A”), make sure you associate it with the same accommodation in your software. Otherwise you end up with duplicate reservations across different properties in the dashboard.

4. Check that the iCal URL is still valid

Portals sometimes regenerate the iCal URL, especially after password changes or security resets. If sync stops working, the first thing to check is whether the URL is still valid. In RegistroViajero you get an automatic notification when a sync fails repeatedly.

”The iCal is not syncing Booking reservations”: how to fix it

Typical symptom: you add the Booking iCal, hours go by, and nothing shows up in the dashboard.

Check, in this order:

1. That the URL is the export iCal, not the import one. Booking offers both. The one you need is the one that comes out of the portal.
2. That the property has confirmed reservations inside the range the iCal exports (Booking publishes up to 12 months ahead).
3. That the URL has not expired. After a password change, regenerate it from the Extranet.
4. That your software has no DNS or outbound HTTPS failure. Force a manual sync and check the log.

If all four are fine and still nothing lands, open a ticket with your provider.

Common iCal problems and how to resolve them

”The reservation shows up with the wrong dates”

Some portals report the end date as the day after checkout (the “up to but not including” convention). Others report the same day as the checkout. The software should normalise this. If you see an extra night, check the time zone and the portal’s convention.

”I want to see the guest’s name but it doesn’t show”

Many OTA portal iCals omit the name for privacy reasons. The actual holder and real data come in when you send the guest the digital check-in link, where they fill in the Annex I details under RD 933/2021³.

”The iCal brings in very old reservations”

By default, most iCals export a wide range (6–12 months ahead and sometimes a few months back). That’s normal. Nothing is imported blindly. Only future or in-progress reservations trigger the creation of a new record.

iCal and RD 933/2021 compliance

Connecting iCal does not replace the duty to send the guest report to the Ministry, immediately and within 24 hours at the latest⁴. What it does is feed your system with reservations so that:

1. The stay is created with the correct dates from minute one.
2. The check-in link reaches the guest without you having to create it manually.
3. When the guest fills in their data and signs, the guest report is generated and submitted automatically.
4. If the guest cancels and the report had already been submitted, the cancellation is also communicated automatically.

iCal is step zero of automation. Without iCal, you have to create each reservation by hand before you can send the guest the check-in.

After the iCal sync: what to set up next

• How to automate guest registration: the full flow, from booking to Ministry submission.
• What RD 933/2021 requires: the full regulatory framework.
• How to obtain SES.HOSPEDAJES credentials: without credentials, no submission is possible.
• Penalties for non-compliance: what’s at stake if you don’t comply.
• Registering minors: specific rules for children and teenagers.

Want to see it working end to end? See how RegistroViajero works: connect your iCal calendars and the reports go out on their own.

The exact menu names on Booking, Airbnb, and other portals may change. This guide reflects the general flow at the time of publication.