Everyone knows that Wave Season (January through March) is a time when cruise lines put out awesome booking promotions — think free upgrades, extra-value offers and fare discounts. But we have also seen some amazing sales in the fall months. That got us wondering: If the autumn months are a time when cruise lines are pushing to sell off remaining inventory for the current year while encouraging cruisers to book early for next year, as well as October being CLIA’s “Plan a Cruise Month,” could fall possibly be a better time to book a cruise than winter?

We put this question to several travel agents, who acknowledged seeing great fall deals in previous years. “Last year, so many companies came out with really amazing tacticals [aka promotions] in the fall,” says Marni Becker, Director of Cruise Sales for Protravel International. “Royal Caribbean had a great promo, and river cruise companies had their best offers in the fall.”

But Becker and others agree that the industry is changing — and it’s hard to predict whether a previous trend will remain. “Promotions are not as consistent,” says Stephanie Serino, a luxury cruise specialist for the Tzell Travel Group. “Rules as to the best time to book no longer apply.”

So is fall the best time to book? It can be — depending on what you’re looking for in a cruise and whether slow sales earlier in the year, or a cruise line drive for early bookings, result in price drops and promos.

If you’re itching for great value, here are three cases when fall is the best time to book.

You want a last-minute Caribbean cruise.

You might have heard this one before: “From September through December, the Caribbean is over-saturated with ships, and there’s less demand,” says Greg Coiro, CEO of Direct Line Cruises. “Cruise lines get very aggressive and drop prices or offer extra value-adds to close off the end of the year.”

If you can be flexible with your travel dates, don’t have a particular need for a certain type of cabin (or are fine with an inside or outside) and don’t mind cruising the islands during hurricane season, you can definitely score a great deal on a last-minute Caribbean cruise by booking in the fall.

You want to book early for the best availability.

Cruisers who are picky about cabin type and sail date want to book early to get their dream cruise. Fall is a key time to book early for next year’s summer and even holiday sailings. Some cruise lines even announce the next season of itineraries during the autumn months.

Booking early is also useful if you’re looking at a limited-supply offering. “A consumer needs to look at the destination they are considering,” counsels Karyn Todd, senior vice president at Cruise.com.

The same applies to specific types of cabins in short supply, such as top-end suites, connecting cabins and staterooms that can sleep three, four or even five passengers. You might not get a rock-bottom rate, but that’s secondary to getting the type of trip you actually want.

Many cruise travelers worry that by booking early, they won’t get the best deal. Travel agents tell us that’s not true. “Many lines have early saver programs, like Carnival,” says Coiro. “If you book seven or eight months in advance, you’ll get an early saver rate that guarantees to be the lowest fare and you’ll get a rate adjustment if fares go down…. There’s not too much risk to booking early, but there can be great reward like a value add or onboard credit.”

“Early bookers get the best deals,” Serino agrees. “Every line lets bookings be adjusted [for price changes] so you’re never penalized for booking early.” She also notes that luxury cruise lines tend to offer their best cruise fares right when they announce new itineraries, so high-end travelers should feel confident committing early.

If you see the itinerary, sail date and cabin type you want in the fall, don’t wait until the winter and Wave Season in hopes of getting a better deal. Book the cruise and be confident that you made a smart purchase.

You see a great promotion.

The cruise lines want to fill their ships as early as possible, and to convince travelers to stop procrastinating on making their vacation plans, they lure you with promotions and promises of the lowest prices. Depending on a cruise line’s sales needs each year, you might very well see some impressive promotions months before Wave Season kicks off.

“For the last few years, smart cruise lines have absolutely come out with some very attractive ‘pre-Wave’ rates as a way to get a bump up prior to the start of Wave Season,” says Todd. “The idea is to reward the consumer who is willing to help them lock in more revenue early on, helping them maintain a higher ‘supply & demand’ price point going into Wave Season.  And, these rates usually come with some additional benefits.”

Becker notes that in 2017, Celebrity Cruises started offering its early-booking promotions in the fall, resulting in a de facto five-month Wave Season sale, and Seabourn also had a great fall sale. She also mentions CLIA’s “Plan a Cruise Month” — October — as a time to look for shipboard credit and other deals for the next year’s sailings. River cruise lines, which typically fill ships earlier than ocean cruises, tend to put out promos in the fall to try and sell off remaining inventory for next spring and summer’s sailings.

Also, just because a cruise line doesn’t have a deal on offer, it doesn’t mean a travel agency won’t release its own booking incentive. Many agencies partner with cruise lines for exclusive offers. Coiro says that Direct Line Cruises’ promotions don’t necessarily follow the same patterns as the cruise lines’. So if the cruise lines are advertising deals for Wave Season or CLIA month, his company might offer its own incentives before or after those times.

How do you know if you’re getting a great fall deal? “The promotions to look for are value adds,” says Serino. “If you’re not choosing a luxury line, a complimentary beverage package is a huge value and makes a difference in what you pay at the end of the cruise; it enhances your experience.” Becker recommends monitoring cruise line’s Wave Season promotions and comparing those to the line’s fall promotions. “If you see just a little onboard credit [during CLIA month], wait for November/December for lines to jump-start their sales,” she says.

And make sure the deal is right for you. If you only drink the occasional glass of wine, an offer of a complimentary beverage package won’t be as beneficial as onboard credit or a cabin upgrade. If you don’t spend a lot of time in your cabin, skip the upgrade promo and look for a value-add like prepaid gratuities or free shore excursions. Just want the lowest cruise fare possible? Know that those deals come with no or fewer extra perks than booking a balcony cabin or suite at a discounted but not rock-bottom rate.

It’s hard to predict if this fall will see an outpouring of amazing deals or just some average early-booking incentives. Either way, if you know you want to cruise next year, it makes sense to keep an eye on the sales from September through December. You might discover a great offer on next year’s dream vacation.