How long does it take to switch hotel PMS?

The cut-over itself can be done in a day. The preparation - exports, mapping room types and rates, training staff on your own data - is what takes time, and it depends on your size and the vendors involved. Ask both vendors for a written plan.

How do I avoid double bookings when changing PMS?

Freeze rate changes, export future reservations as late as possible, import and check counts per night, connect channels to the new system before disconnecting them from the old one, and close channels briefly if there would otherwise be a gap.

What data should I export from my old hotel PMS?

Every future reservation with guest contact, rate, deposit and requests; guest profiles and stay history; rate plans, room types and restrictions; and open folios and unpaid balances. Get the format and timing in writing before you sign with the new vendor.

Should I keep my old PMS after switching?

Keep read-only access for at least a month, until reports from the new system match your accounts. You will need the old records to answer questions about past stays and payments.

How to switch hotel PMS without losing bookings: a step-by-step plan

The risk in changing systems is not the new software. It is the week when two systems both think they own your availability.

Hotels stay on software they dislike for years for one reason: the switch looks dangerous. It is, if it is done as a single leap. Done as a sequence, it is mostly paperwork.

The one thing that goes wrong is always the same: for a period, two systems both believe they own your availability, and a room sells twice. Everything below exists to make that period as short and as controlled as possible.

Before you sign: get the exit and entry in writing

From the old vendor, ask for a full export of:

every future reservation (with guest contact, rate, deposit paid, special requests);
guest profiles and stay history;
rate plans, room types and restrictions;
open folios and unpaid balances.

Ask in what format, and how long it takes. If the answer is "we can't export that", you have learned something about the vendor, not about switching.

From the new vendor, ask what they import, in which format, and who does the mapping. "We can import anything" is not an answer; "send us a CSV with these columns and we map room types with you on a call" is.

Pick the cut-over day on purpose

Choose a day with few arrivals and departures, not a quiet week in general. The front desk will be learning while working; give them the lightest shift you have.

Tell your staff the date two weeks ahead, and train them on the new system with your own data before it goes live.

The sequence that avoids double bookings

Freeze rate and restriction changes in the old system from the day before.
Export future reservations from the old system as late as possible — the evening before.
Import them into the new system and check the counts per night against the old system.
Connect channels to the new system, and only then disconnect them from the old one. With a channel manager this is a mapping change; without one it means updating each OTA extranet.
Close every channel for one hour if you cannot do step 4 without a gap. One hour of no sales costs less than one walked guest.
Compare availability night by night for the next 30 days between the new system and each OTA extranet.
Keep the old system read-only for at least a month. You will need it to answer "what did we charge this guest in March".

After go-live

Reconcile deposits: every prepaid booking in the old system must show the same amount received in the new one.
Watch for bookings that arrive in the old system from a channel you forgot to move. There is usually one.
Only cancel the old contract when a month of reports from the new system matches your accounts.

How to switch hotel PMS without losing a single booking