Missing the boat on a summer cruise could turn out to be a blessing in disguise as a handful of cruise lines are offering big savings and special offers on upcoming fall sailings for a limited time this summer.

Uniworld Boutique River Cruise Collection is offering picture-perfect deals on upcoming 2018 cruises all over the world, including voyages through Europe, Asia, Egypt and India. For a limited time, travelers can save up to $2,000 per stateroom.

Holland America Line's Explore4 offer is available on 600-plus 2018-2020 sailings booked by November 19. Passengers can benefit from a Signature Beverage Package, Pinnacle Grill dinner, free or reduced fares for third/fourth guests and a 50 percent reduced deposit on any stateroom while guests booking suites receive an additional $200 of onboard spending money.

A luxury sailing with Windstar Cruises is arguably the best way to experience Tahiti and French Polynesia and right now travelers can take advantage of the line's cruise, airfare and hotel offer which includes roundtrip airfare from Los Angeles to Papeete, an overnight and daytime hotel stay at Le Meridien Papeete Hotel as well as transfers between the airport, hotel and Wind Spirit yacht.

Book a sailing to Antarctica, Australia and New Zealand with Seabourn by August 13 and capitalize on special offers such as a complimentary Three Veranda Suite Category upgrade, a complimentary Veranda for Ocean View Suite Category upgrade and a complimentary 300-minute Internet Package per person. Meanwhile, passengers booking penthouse or premium suites can receive a complimentary Unlimited Internet Package per suite along with $1,000 per suite shipboard credit.

Celebrate Thanksgiving 2018 on a one-of-a-kind luxury cruise aboard Crystal Serenity from Fort Lauderdale to Los Angeles. Crystal Cruises' 16-day Thanksgiving Tropical Treasures sailing departs November 21 and features stops in the Bahamas and Colombia prior to traversing the Panama Canal en route to Central America, Mexico and, finally, the U.S. Book by August 31 and save some hard-earned cash for the holidays.

Crystal Cruises' 14-day Pacific Coast Panorama voyage departs December 7, sailing roundtrip from Los Angeles to coveted destinations such as San Francisco, San Diego, Cabo San Lucas and Puerto Vallarta, among other places. Guests can also save on this sailing when they book by the end of August.

Book a 12-day roundtrip cruise of the Norwegian coast with Hurtigruten and you're guaranteed to see the Northern Lights or come away with a free cruise. If guests don't experience the aurora borealis during their sailing, they will receive a complimentary a six- or seven-day cruise.

AmaWaterways is offering free flights to Europe for upcoming fall cruises when passengers book by August 31. Mention promo code "FLYFREE" at the time of booking to get complimentary roundtrip airfare from dozens of U.S. and Canada gateways for scenic voyages along the Danube, Rhine and Moselle rivers.

Want to enjoy a river cruise without needing a passport? American Queen Steamboat Company is offering significant savings on its upcoming holiday river cruises through the U.S., including up to $1,600 per stateroom on select voyages in November and December. The offer expires August 31.

Now through the end of July, Paul Gauguin Cruises is offering up to $500 shipboard credit and a reduced deposit of $250 per person on select sailings in the South Pacific. The cruise line is also offering savings of 50 percent off standard all-inclusive cruise fares plus included roundtrip airfare from Los Angeles.

While availability is certainly limited, there's still a little bit of time to book upcoming October sailings on the Rhine between trendingAmsterdam and Basel. Prior to July 31, travelers can score two-for-one cruise plus air from $299 on Viking River Cruises' 2018 Rhine Getaway.

Experience the World's Most Awarded Luxury Cruise Line at a discount this fall when you book your Crystal Cruises river voyage by September 30 and save up to $1,000 per guest. Fall sailings range from six to 16 days and include destinations like Amsterdam, Budapest, Frankfurt and Vienna, among others.

Travelers can receive free airfare in addition to saving $1,000 per couple on select European river cruises with Avalon Waterways this fall, including voyages along the blue Danube and the romantic Rhine.