It’s the biggest holiday promotion in the world.
But where does it come from?
How much does it cost?
And what does it offer?
That’s the subject of our BBC News special “Free” nights, where we explain how to get the most bang for your buck.
How to apply?
You’ll need a Marriott Rewards Card, a valid US bank account and a US credit card.
Find out more about how to apply.
What do I need to get?
Marriott offers two free nights: the first two nights are booked directly from Marriott by your hotel, and the rest are booked through Marriott’s website.
There’s a maximum of three nights.
For example, if you book a second room for a family of four at a Marriott hotel in the US, you’ll get a free night.
To find out more, see our guide to free night rates.
How much do they cost?
Marriott’s promo codes are valid from 30 November 2018.
You can apply for the first free night for as little as $19 a night, and as much as $60 a night after that.
There are also a couple of other perks: you’ll receive a bonus of up to $250 (£205) on the first booking, up to a maximum annual reward of $1,000 (£800) per person.
You’ll also be eligible for a free room voucher.
How do I use it?
You need a US bank or credit card to make your booking.
Booking is only possible online.
Once you’ve booked, the promo code will appear on your Marriott Rewards card.
The booking process is straightforward, so there’s no need to call Marriott to book a room.
Just click on the code on the card and follow the instructions.
If you’re using the Marriott Rewards app, you can then redeem your Marriott Promotional Code at a number of participating Marriott hotels.
How does it work?
Your first free day is usually booked in your first hotel, but you’ll have a chance to redeem the promo codes at additional hotels.
For instance, if your first free room is at the Hilton Garden Inn in Washington, DC, you’d be able to redeem your first promo code for $3,000.
If your first day is at a hotel in Dallas, you could get up to 10% off your first booking.
To redeem the code, just click on it in your card details.
What are Marriott’s terms and conditions?
All Marriott promotional codes are non-transferable.
You must contact Marriott to redeem them.
Marriott also provides a hotel booking page with additional details, including hotel details, contact details and a link to a hotel search tool.
What happens if I use my promo code?
Marriott says that it won’t take your card, your booking details or your booking voucher back.
If Marriott uses your hotel booking details to book your next hotel, you might be able a refund or credit for your unused hotel nights.
This is because the company doesn’t use credit or debit cards to book its hotels.
Marriott’s promotional codes aren’t transferable.
If the code isn’t redeemed, you’re still able to get a refund.
For hotel booking purposes, the hotel you booked in is considered your hotel.
Marriott can’t be held liable for cancellations.
How can I avoid spending money on my hotel night?
As with most hotel promotions, Marriott’s hotel booking system doesn’t require you to book an entire room.
If, for example, you’ve been told that you can book up to three nights for a total of $30 a night before booking a free day, you should avoid booking any room with a higher minimum room rate.
That’s because Marriott’s promotion codes are only valid for the initial booking of a hotel.
So if you’re booked through the Marriott website, you won’t get any credit for the room you booked.
However, you still have the option to book more nights.
You’d still need to make a booking from your hotel account, so you could then book up again if the hotel’s minimum room rates drop.
How will Marriott know I’ve booked my free nights?
If you use your hotel’s booking system to book free nights, Marriott will send a message to your email address, so if you click on your message, Marriott can see that you’ve done so.
This means that Marriott can look into your booking history to see whether you’ve already booked the next room you’re booking, or if you have more free nights to choose from.
The messages are only sent once per day, so once you’ve used your free night, Marriott won’t be able the email to track your activity.
How often will my free night be given out?
Marriott doesn’t give out free nights by the hour.
However they will give out any night that is booked by the end of the day.
For hotels with limited capacity, Marriott may offer a free nights credit if you’ve exceeded the number