About the Messaging API

The Messaging API acts as a communication bridge between your travellers and accommodation, enabling post-booking interactions once a reservation is created.

The /messages API collection

The Messages API collection is seamlessly integrated into Demand API - Accommodation API collection, and enables secure, structured, and context-aware post-booking communication between accommodation hosts and guests, specifically tied to reservations.

Features

The Messaging API supports a wide range of capabilities:

Capabilities of Messaging API includes two way communication, contextual conversations, conversation history and file attachments

Who is this for?

We recommend Messaging API integrations to existing Demand API Affiliate Partners who wish to provide a better post-booking experience that boosts loyalty and trust, while reducing customer services inbound.

Integration options

The Messaging API supports flexible integration approaches to suit a variety of partner needs.

Whether you're sending welcome messages, managing two-way conversations, or exchanging attachments, the API provides the necessary endpoints to build a seamless messaging experience into your system.

Available integration modes	Description
✅ Send messages	Send text messages from partners to guests, optionally with attachments.
✅ Receive messages	Retrieve incoming messages either by conversation or via latest polling.
✅ Message threading	Maintain full conversation context using `conversation`.
✅ Attachments	Upload images to send with messages or download attachments from guests.
✅ Conversation metadata access	View details about message participants, timestamps, and message status.
✅ Reservation-based context	Use reservation ID to filter or identify message threads for specific stays.

Benefits of integrating the Messaging API

Integrating the Messaging API into your system can bring some benefits such as:

Key benefits of Messaging API includes scability, data for optimisation, loyalty boost and seamless integration

The communication flow

Two-way communication is enabled after a reservation is created. Either party—traveller or host—can initiate contact.

Accommodation to traveller

1. The accommodation sends a "welcome message"

Accommodation can use Booking.com extranet messaging centre or any other defined channel.

2. Affiliate partner system uses Messaging API to:

Deliver messages to travellers in the defined channel (example: by email) via the messages/send endpoint.
Fetch all messages from the property through Messaging API using the /messages/latest and /messages/latest/confirm.

Common accommodation messages

Property may communicate with the guest around the following topics:

Topic	Examples / Details
Welcome messages	Greet the guest, introduce the property, confirm the booking.
Respond to special requests.	Reply to specific bed/room arrangements, parking availability requests, etc.
Confirm available amenities.	Provides details on facilites such as Wi-Fi, kitchen, air conditioning, laundry, or accessibility features.
Inform about local taxes	Requests about tourist or city taxes charges.
Provides local recommendations	Share information about nearby attractions, restaurants, shops, or tours and activities.

Example of welcome message sent via the Booking.com platform:

auto-reply welcome message

Traveller to Accommodation

1. Travellers may start the conversation by sending a message

2. Affiliate partner system uses Messaging API to:.

Deliver messages from/to travellers in the defined channel (example: by email) via the messages/send endpoint.
Fetch all messages from the property through Messaging API using the /messages/latest and /messages/latest/confirm.

Common traveller messages

Travellers may communicate with the accommodation around the following topics:

Topic	Examples / Details
Check-in details	Estimated arrival and departure times (checkin/checkout times) Early or late check-in requests. Self check-in instructions or key collection info.
Directions & transport	Request directions to the property. Parking availability. Request airport transfer info.
Booking modifications	Requests about date or guest changes. Clarify cancellation and refund policies.
Amenities & services	Confirm availability of Wi-Fi, kitchen, air conditioning, laundry, or accessibility features.
Special requests	Requests for baby cots, extra beds, dietary needs, or celebration-related setups. Multiple rooms to be located near each other.
Local recommendations	Request about nearby attractions, restaurants, shops, or tours and activities.
Payment & charges	Confirm accepted payment methods, deposits, or tourist/city taxes.

Message delivery channels

Messages sent via the Messaging API can be delivered through a wide range of channels based on your particular setup and/or preferences:

Participant	Where messages appear
Guest	In-app (Booking.com app) email partner Messaging centre AI or automated assistants (if available).
Accommodation (property)	Extranet Messaging centre email notifications, or via connected systems (channel manager / PMS) through API.
Partner (you)	Via Messaging API calls (/messages/conversations, /messages/latest, /messages/latest/confirm, /messages/send, etc.)

Affiliate partners responsibilities

As a Managed Affiliate Partner integrating the Messaging API, you are responsible for ensuring successful message delivery to the end user.

You must:

Guarantee reliable delivery of all messages sent through the API.
Display messages clearly and without delay within your platform.
Minimise delivery issues, which could negatively affect guest experience and partner performance.

Available endpoints

Messages endpoints

Endpoint	Use it to ...
/messages/send	Send a new message starting a new conversation, or add a message to an existing conversation thread.
/messages/latest	Retrieve the latest messages across all conversations (up to 100).
/messages/latest/confirm	Confirms the message was received. This is required in order to receive new messages from POST /messages/latest.
/messages/conversations	Retrieve the conversation history for the authenticated user up to 1 year after checkout.

Attachments endpoints

Endpoint	Use it to ...
/messages/attachments/upload	Upload an image to a conversation (for files smaller than 1MB).
/messages/attachments/metadata	Retrieve details about a previously uploaded image, such as name, type and size.
/messages/attachments/download	Download an attachment.

What's next

Read the following guidelines to start getting familiar with the Messaging API:

Get started - Try the messaging endpoints
Refer to our detailed guides for Messaging API examples and best practices:
- Manage messages
- Manage attachments