Here's how you can use your Costco membership to book a cruise

Once you've gone to the Costco Travel website, you can narrow the options you're given if you have criteria in mind. Otherwise, you can browse the cruises that are available in a given month. The month of departure is the only criterion you need to specify.

Once you've decided what you're looking for, you'll be shown the options that meet your criteria. This page gives you a snapshot of other relevant information, like the per-night prices for different rooms, the ship's features, the ports of call it will stop at, and an overall rating for the cruise ship from the travel guide company Berlitz.

For some cruises, you won't be able to see prices unless you enter your Costco membership number.

Once you've decided on a cruise, specify how many rooms you want, how many people will be staying in each room, and each passenger's age. You can also note if anyone in your party qualifies for a senior discount or is a member of the cruise line's loyalty program.

You can decide the size of the room you'd like, your room's location, and whether you want a room with a view outside the ship.

You can also purchase flight tickets and hotel reservations for before and after the cruise. While Costco will make a recommendation, you can switch to another option if you'd like.

Costco says it does not offer tickets from all airlines in every market, so you may have to book flights separately to get the best price.

From there, you'll land on an order page where you can review and confirm your reservation.

If you're booking a cruise with Viking River Cruises, you'll have to pay the full cost of the trip at the time you make your reservation. Otherwise, full payment will be due 90-160 days before the cruise, depending on the cruise line. If full payment is not due at the time of your reservation, you'll pay a deposit.