One of the major stumbling blocks for travellers looking to take a river cruise by themselves is the dreaded “single supplement.” River cruise companies base their advertised prices on double-occupancy, and when only one person wants to occupy a stateroom, that price often rises – to the point where you could end up paying for the second guest you’re not bringing with you.

But when it comes to single supplements, policies between river cruise lines can vary wildly – and, as solo travel gains broader recognition, river cruise lines have been proactive at reducing – and even eliminating – the single supplement on select cabins, sailings and itineraries.

It’s important to know that these waivers may be limited to certain departure dates or cabin categories; typically, if you’re going after the top-of-the-line suites and balcony staterooms on a river cruise ship, you’ll always pay the full single supplement that is the equivalent of paying for you and your phantom guest.

Additionally, some companies offer solo traveler savings only if you choose to be paired with a roommate (of the same sex) or if you stay in a stateroom designed exclusively for single occupancy – and there aren’t many of those on the rivers just yet.

Industry juggernaut Viking River Cruises doesn’t offer single-occupancy staterooms on any of its popular Viking Longship river cruise vessels, but the line does offer single supplements that range between 150 percent (mostly riverview staterooms), with 200 percent being the norm for the more-desirable balcony staterooms and, of course, the line’s massive Explorer Suites.

All of the major river cruise lines – AmaWaterways, Avalon Waterways, CroisiEurope, Scenic, Tauck, Uniworld Boutique River Cruise Collection and Vantage – frequently offer specials that will either reduce or eliminate the single-supplement on select sailings. Much of this is capacity-controlled, and offers can sometimes be regional in nature. For example, guests booking their cruise from Canada, the United States or Great Britain will frequently be offered different deals and pricing schemes, so it always pays to check with your local travel agent, who will have a better idea of what specials are currently running.

While these specials used to be uniquely-timed to be available only during select periods, we’ve found that most river cruise lines always have some sort of special going on. If a particular cruise doesn’t offer a substantial single supplement, it may offer other value-added perks, like reduced or free economy class airfare, beverage packages, or pre-and-post-cruise hotel stays.

While pairing guests is more common on the ocean cruising front, some river cruise lines still offer to match up solo travellers with a roommate. For example, American river cruise and tour operator Grand Circle will waive its single supplement fee for guests who participate in the “FREE Roommate Matching Service.” With this program, you agree to be matched with a same-gender roommate in exchange for the elimination of the single supplement. If the river cruise line can’t match you with someone of the same sex, you get to occupy the stateroom as a single occupant but won’t have to pay the supplemental fee.

Grand Circle’s standard single supplement is about 125 percent of the regular per-person rate for European river cruises; a modest increase that doesn’t penalize the solo cruiser. Some itineraries, like Grand Circle’s Yangtze River cruise, carry no single supplement (likely due to the fact that this multi-week cruisetour takes place primarily on land).

Other river cruise companies will provide some type of discount if you are traveling solo, but some are not quite as generous with their single supplement rates as the previously mentioned companies.

On American Cruise Lines, solo cruisers typically pay between 150 percent and 175 percent of the advertised double-occupancy rate, depending on class of stateroom chosen.

The American Queen Steamboat Company, on the other hand, features a limited number of single-occupancy staterooms that can be booked without a supplement. If these are taken, standard double-occupancy cabins can be booked for between 150 percent and 200 percent of the advertised per-person rate.

Ultimately, what you’ll pay as a solo traveler depends on what you’re seeking. You might prefer a specific company or itinerary that does or does not offer special solo traveler rates. Keep in mind that it’s best to book early if you’re a single traveler, especially if you are looking for a single stateroom. Not all river cruise ships have single cabins, and those that do, have a limited supply.

A solo travel package is one way to save. When comparing packages, however, consider the bigger picture. Some river cruise lines offer more inclusive pricing than others. All things considered, you may be able to get a good rate on an all-inclusive vessel, even if you are charged a hefty single supplement fee.