Of the more than 20 million Americans who go on cruises each year, 20% bring kids aboard, according to researchers.
And, in our experience, approximately 100% of those seafaring youngsters will want to splash in the pool the second you've settled into a waterside lounger for a nap.
There are, however, some options for travelers who prefer a cruising experience sans rug rats.
As a matter of fact, one major line went adults-only just this month, joining a small cadre of cruise companies that restrict sailings to passengers who are old enough to vote.
Then there are the lines—often toward the luxury side of the industry—that aren't strictly adults-only but might as well be, considering how little they cater to little ones.
Even many of the big, so-called mainstream cruise lines often have areas of ships set aside for grown-ups seeking a break from the relentless family-friendliness elsewhere on board.
If you, too, are an adult who likes the idea of taking a kid-free cruise, here are your best bets.
Adults-only cruise lines
Oceania Cruises announced earlier in January that it will only welcome customers aged 18 and older from here on out.
The company made the decision based largely on customer feedback, according to a news release. "Guests choose Oceania Cruises for its serene atmosphere, sophisticated service and unhurried pace, traits that are highly sought after and valued by mature, affluent travelers," the statement explained.
With a customer base that already has an average age in the mid-60s, Oceania doesn't expect the policy change to have a huge impact on either the bottom line or the passenger experience, Oceania's chief commercial officer, Nathan Hickman, told USA Today.
“I'll be honest with you, a good segment of our guests already thought we were adult-only," Hickman told the newspaper.
Likewise, the ocean, river, and expedition cruises offered by Viking don't allow passengers under 18.
As with Oceania, Viking's target demo is older and well-to-do—though there are noteworthy distinctions between the two lines.
As Travel Weekly points out, Viking cruises are usually more expensive, a bit more slow-placed (you'll look in vain for an onboard casino), and centered on programs and excursions designed to teach passengers a lot about the destination's local culture.
Oceania, for its part, goes out of its way to wow guests with its culinary offerings.
The third major adults-only line is Virgin Voyages, which was initially marketed as a trendy, party-hearty, Hard-Rock-Hotel-at-sea type of alternative to mainstream cruising.
Though Virgin remains adults-only, Frommer's has found you don't have to be a party monster to enjoy the brand's cruises, and Virgin now strives to cater the vibe to guests wherever they fall on the hermit–social butterfly spectrum, with offbeat entertainment options, meditation classes, what have you.
In the United Kingdom, there are a handful of additional cruise lines that offer adults-only sailings: Saga (intended for passengers aged 50 and older), Ambassador Cruise Line, and, on certain ships, P&O Cruises and Marella Cruises.
Cruise lines that aren't adults-only but might as well be
Many luxury and small-ship cruises don't expressly forbid children—but don't exactly roll out the welcome mat for kiddos, either.
If the line you're considering makes a big deal about its cuisine, educational or cultural programming, and luxe accommodations, but lacks a kids' club or ships loaded up with waterslides, arcades, go-kart tracks, and other rides and games that make you think of an amusement park, it's likely that kids aren't a priority for that cruise line and there probably won't be many minors on board.
Among the brands that fall into this category are AmaWaterways, Azamara, Crystal Cruises, Seabourn, and Windstar Cruises.
Mainstream cruise lines that have adults-only areas on ships
Finally, the biggest, most popular cruise lines also recognize that grown-up passengers might want a break from kids (including, and maybe especially, their own).
But on these ships, the child-free condition will only be temporary—and sometimes costs extra.
Carnival Cruise Line's Serenity Adult Only Retreat is a free-to-access sundeck with a bar for passengers ages 21 and older. (Carnival has also begun experimenting with separate, adults-only sailings.)
Royal Caribbean has no-kids-allowed spaces like the indoor pool/whirlpool/lounge area called the Solarium, while Norwegian Cruise Line's adults-only areas range from the Spice H20 bar to the paid-access Vibe Beach Club.
Additionally, Norwegian and other lines that have cabins for solo cruisers might appeal to adults hoping to minimize their interactions with small fry. Solo travelers sometimes get access to their own dedicated lounge where they can hobnob with their fellow adult singletons.
Princess Cruises, Holland America Line, and Celebrity Cruises restrict certain areas on ships to passengers over 18 as well. Celebrity in particular cultivates a more sophisticated atmosphere than you'll find on the floating-theme-park ships.
Even Disney Cruise Line outfits ships with pools and dining experiences tailored exclusively to adult passengers.
But if you want to get through your whole trip without laying eyes on a youngster, Disney probably isn't the safest choice.