Rezlynx API overview

Introduction to the Rezlynx API

The Rezlynx API is the Public API for the Rezlynx PMS, by which external parties (customers, partners and collaborators) can interact and share data with the system. It can be used for posting charges to rooms and guest folios, getting information on guests checking in to the property, and much more besides.

The API is a Web API based on the Web Services standard, using SOAP over HTTP(S). The service is described in machine-readable WSDL format. Services are called using API METHODS described in serialised XML.

Although RESTful APIs using JSON formatting are currently more popular, SOAP/XML remains the industry standard within hospitality, travel & leisure. It is the standard adopted by the OTA and HTNG.

MoreGlossary of terms


The set of API methods covers many but not all functions of the Rezlynx PMS. The most common use cases are considered in Workflows and include point-of-sale, telephones, door locking systems and spa systems, to name just a few.


In particular, what is not in scope is checking availability, making reservations and setting room rates, which is covered instead by the companion Roomlynx API. Roomlynx is the distribution product module which works alongside Rezlynx PMS and manages the interfaces with booking channels such as online booking sites and global distribution systems (GDSs).

The Roomlynx API is not covered by this wiki. For information on Roomlynx and the Roomlynx API, please contact your Guestline representative.

Bulk import

Also out of scope is bulk import of data. For example, the API is suitable for querying individual reservations but if two years' worth of reservations data is needed, then the API is not the tool to do that. For assistance with your particular requirements, contact your Guestline representative.

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