The Port of Miami

Many last-minute bargain cruise fares are going to be for sailings out of the high-volume Port of Miami. (Richard Sheinwald / Bloomberg News)

It's not too late to get a deal on a cruise vacation for summer or fall. Cruise lines use yield management — increasing or (in this case) decreasing a price in response to demand, among other factors — to fill their cabins, so some of the best deals in cruising are offered within 90 days of the sailing if cabins need to be filled.

As is always the case with rock-bottom prices, there are a few considerations. The prices are almost always for inside cabins (as is the case of the ones we found here), which may not be the best choice for those planning to spend a lot of time in their cabin. If you want to upgrade to an outside cabin, you can usually get one for a bit more money. (A balcony cabin, however, is often substantially more.)

The rates listed are always per person, based on two people to a cabin, so you'll need to travel with someone or expect to pay a single supplement if you want the entire cabin to yourself.

These best-price sailings are most often out of Miami, where the biggest volume of cruise departures takes place, so you have to factor in the cost of airfare. (Fly.com's airfare calendar showed fares from LAX to Miami as low as $339 on some dates.)

The sailings are usually short, and the vessels are often older ships. If you have heard that a line is known for, say, a partnership with a celebrity chef or a fun new water slide, don't assume you'll have these amenities.

Think too about what's included in the cruise fare and what's extra. These fares include the cruise itself, some entertainment, plus basic meals in the main dining room and Lido Deck buffets. If you want cocktails or beer, that probably will be extra, as are shore excursions, specialty restaurants, airport transfers and gratuities.

These offers tend to go quickly, so act fast when you see a deal you like. Sometimes, only a few inside cabins are available at the teaser price. Here are some of the best rates on offer right now. Note that because the fares go quickly, these may have expired, so try looking at fares just before and just after the dates you're considering.

MSC Cruises, seven nights, from $349: Some of the best deals this year have been on Italy-based MSC Cruises' latest ship, Divina, which launched in November. It sails seven-night eastern and western Caribbean itineraries out of Miami. Dates for that $299 per person fare: sailings on Aug. 23 and Sept. 6.

Info: MSCCruisesUSA.com, (877) 665-4655

Carnival Cruise Line, three nights, from $179: This short sailing on Carnival Ecstasy starts in Miami and calls in the Bahamas. The 23-year-old Ecstasy is one of the line's oldest vessels. It may feel a bit dated and lack Carnival's newer amenities (such as Guy Fieri's burger spot or the Blue Iguana poolside taco bar), but it has been well maintained and doesn't feel worn or threadbare. Sailings are Sept. 8 and 15.

Info: Carnival.com, (800) 764-7419

Norwegian Cruise Line, two nights from $189: This short sailing on Norwegian Sky (which launched in 1996) cruises out of Miami to Nassau and Great Stirrup Cay, the line's private Bahamian island, on Friday. Of course, a cross-country flight is a lot to take on for a two-night sailing, so consider combining this with other activities.

Info: NCL.com, (866) 234-7350

Royal Caribbean: three nights from $279: Majesty of the Seas (built in 1992) is sailing Aug. 22 from Miami to Nassau and CocoCay, the line's private Bahamian island. Note that some of these interior cabins are as small as 159 square feet.

Info: RoyalCaribbean.com, (866) 562-7625

Costa Cruises, six nights from $499: If you want to lock in a great deal now but travel later, this weeklong western Mediterranean cruise on the Costa Serena is tough to beat. The trip departs Nov. 16 and sails from Savona, Italy, to several Italian ports (La Spezia for Cinque Terra, Civitavecchia for Rome, and Naples) and then to Barcelona, Spain, and Marseille, France, before returning to Savona. Just be sure to factor in the expense of flying into Genoa or Milan, Italy, or Nice, France, and transferring to the smaller port of Savona when you are determining the cost of this pre-Thanksgiving vacation.

Info: CostaCruise.com, (800) 462-6782

Sherri Eisenberg is editor of Bon Voyage, an online travel magazine about cruising published by Cruiseline.com.

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