Are you close to booking a Celebrity Cruises voyage? You might want to pay for it with an American Express card.

This month some American Express cardholders can get 35,000 bonus Membership Rewards points when spending $1,000 or more on a Celebrity cruise.

That’s a significantly large number of Membership Rewards points. TPG currently values Membership Rewards points at 2 cents each, meaning that the 35,000 bonus points would be worth $700 at our valuation.

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To put it another way, if you spend $1,000 on a Celebrity sailing using an American Express card, you’ll get 70% of that money back in Membership Rewards points.

Note that this is a targeted offer, which means not every cardholder has received it. Also, you must enroll in this specific Amex Offers deal in order to redeem it.

You also need to act quickly. The offer expires March 31.

Other caveats include the stipulation that cardmembers can only enroll in the offer with one American Express card. In addition, the offer is only valid on cruise bookings made online, by calling 844-530-3783 or through a travel agent. Reservations must be booked on U.S. websites only.

Related: The ultimate guide to Celebrity ships and itineraries

The offer is only for the Celebrity Cruises brand and not its Royal Caribbean Group sister brands, Royal Caribbean and Silversea Cruises.

The 35,000-point Celebrity offer is just one of at least two Celebrity-related offers that have popped up for American Express cardholders since January. Some American Express cardholders have also seen an offer for $175 back when spending $500 or more on a Celebrity cruise. That offer also expires March 31.

Some examples of Amex cards where you might receive these Celebrity offers are:

To find out if you are eligible for the offer, check your American Express card account. If you see the deal, it’s best to add it right away, as it might disappear. Some offers are capacity controlled.

Another tip: Only 100 Amex Offers are visible at one time. So, if you’re at capacity, add offers to your card and new ones may appear.

Also, don’t forget that if you need to fly to or from your cruise port, Amex Travel will give you 5 points per dollar on flights booked directly with airlines (on up to $500,000 on these purchases per calendar year) and 5 points per dollar on prepaid hotels booked on Amex Travel.

Related: The 5 best places you can visit on a Celebrity Cruises ship

If you’re not an American Express cardholder, you might consider applying for one. The Platinum Card from American Express is offering a welcome bonus of 80,000 Membership Rewards points after you spend $6,000 on purchases within the first six months of cardmembership.

You may also be eligible for a targeted 125,000- or 150,000-point bonus offer using the CardMatch tool (offers are subject to change at any time).

If the Platinum Card isn’t for you, read our guide on choosing the best American Express card that suits your style.

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