What Is a Central Reservation System (CRS)?
A central reservation system (CRS) is software a hotel or hotel group uses to manage room inventory, rates and reservations from one place. It sends that availability to every connected channel, such as OTAs, the GDS and the hotel's own website, and passes each booking back to the property management system.
Last updated: October 2026
How a central reservation system works
A CRS sits above the property management system (PMS) in a hotel's technology. The PMS runs the property: check-in, check-out, room assignments and billing. The CRS handles distribution.
The CRS holds what the hotel can sell: which rooms are open, at what rates and under which conditions. It pushes that to every connected channel, including "OTAs, GDS, the hotel's own website, and call centres." Inventory and rates then sync in both directions between the CRS, the channels and the PMS (SiteMinder).
The CRS connects to the channels so the PMS does not have to, then sends each booking back to the PMS (Inntopia). It pulls OTA, direct and travel-agent bookings into one place and also handles group blocks and rate parity.
Here is a typical path. A travel agent books a room through a GDS. The reservation reaches the CRS, which lowers availability on every other channel and sends the booking to the PMS at the property. The front desk sees it there when the guest arrives.
The idea came from airlines. American Airlines and IBM began the SABRE venture in 1959, launched it in 1960 and finished it in December 1964. It was "the world's first online transaction processing system" (Wikipedia). These systems "were later extended for use by travel agencies, and global distribution systems (GDSs)", and most airlines have since outsourced their CRS to GDS companies (Wikipedia). In air travel the same letters often stand for computer reservation system.
Why it matters for hotel distribution
A CRS earns its place when one team sells many rooms through many channels. It is built for chains and groups that manage inventory across many properties. For one independent hotel, a PMS with a built-in channel manager usually covers what a CRS would add (Roommaster). Every hotel needs a PMS; only some need a CRS (Mews). The line keeps moving, because some CRS functions are now built into PMSs (Inntopia).
For a chain, the CRS is where a rate change is made once and reaches every hotel and every channel. That is also where the cost case sits. A CRS supports direct and travel-agent bookings alongside the OTAs, which can cut reliance on "OTAs that charge 15%-25% commissions" (Mews).
The best-known hotel CRS products include OPERA, SynXis and Amadeus (DT). SynXis shows how central these systems are to the industry. It began in 1996 as an early hotel CRS built for the internet (HSMAI). Sabre bought SynXis in 2005 and sold the business that runs it to TPG for $1.1 billion in July 2025 (PhocusWire). At the deal's announcement, the unit served "more than 40% of the world's leading hotel brands", and Sabre kept its GDS business (Hotel Dive). In January 2026 that business took a new name, Aven Hospitality, with SynXis still at its core (Hospitality Net).
Newer channels, such as home-sharing platforms, can also connect at the CRS, so they sell the same rooms and rates as every other channel. Our SynXis channel manager guide shows that setup on one CRS, and the modern hotel tech stack post shows where the CRS sits among the other systems.
CRS compared with a PMS, channel manager, GDS and booking engine
| CRS | PMS | Channel manager | GDS | Booking engine | |
|---|---|---|---|---|---|
| What it is | Central store of rooms, rates and reservations | The hotel's operations system | Software that syncs a property's channels | A booking network for travel agents | The booking screen on a website |
| Main job | Distribute inventory and rates to every channel | Check-in, check-out, room assignments, billing | Distribution to OTAs | Broad distribution to travel agents | Show inventory and take the booking |
| Typical user | Chains, groups and larger hotels | Every hotel | Single properties | Travel agents and corporate booking tools | Guests booking direct |
| Connects to | GDS, OTAs, website, call centre, PMS | CRS or channel manager | OTAs, PMS or CRS | CRS or connectivity provider | CRS or PMS |
The closest neighbour is the channel manager. A CRS works "in much the same way as a channel manager" and "generally has more features than a standalone distribution solution" (SiteMinder). Our post on what a hotel channel manager does covers that side in depth.
Frequently asked questions
What is a central reservation system in a hotel?
How does a central reservation system work?
What is a central reservation system in the front office?
What is the difference between a CRS and a PMS?
What is the difference between a CRS and a GDS?
What is the difference between a CRS and a channel manager?
Related terms
See all termsWhere Jetstream fits
A CRS gives a hotel group one master record of its rooms and rates. Every channel the group sells through, from the GDS to OTAs, metasearch, home-sharing platforms and its own website, needs that record kept current. Jetstream builds an AI channel manager that connects a property's central reservation system (CRS) to the channels where guests book, and keeps inventory accurate on each one. It integrates with the CRS platforms that large hotel groups already run on.