Most people don't know the difference between a published and a non-published airfare. But before you buy an airplane ticket, this information may be helpful to you. Published fares are what you see on airline websites and flight tracking sites like Skyscanner, Orbitz, Expedia, TripAdvisor, and Priceline. Meanwhile, unpublished fares are special discounted rates that are only attainable through travel agents or all-inclusive tours or packages—you cannot find these fares on your own.
Published Airline Fares
Basically, a published fare is one that is available for purchase by anyone. You could call the airline, or check for prices online, and published fares will be immediately available for purchase.
The rules of such fares are readily available and if there is more than one airline offering the same fare you can count on the rules being virtually the same. A non-refundable fare requiring advance purchase of 14 days and a minimum Saturday night stay would be typical of the rules for published fares. Seat sales launched by airlines are considered published fares as well since (subject to seat availability) such airfares are offered to the public.
There are several types of published fares for airlines which include unrestricted full fares (meaning you have flexibility to change or cancel tickets), discount fares, and excursion fares. Through fares are another kind of published airline fare that offers discounts to passengers willing to layover in the airline's hub city. For example, Icelandair and WOW Air both offer affordable flights from America to Europe but often has layovers in Iceland (and encourages travelers to explore beyond the airport by helping them plan transportation and activities during the layover). The main point to be made in advising travelers is to be sure and read the fine print on all published fares so you know the limitations you'll be agreeing to when you purchase your ticket.
Unpublished Airline Fares
Unpublished fares are an entirely different beast and are not something every traveler knows about. They may be seats that a consolidator purchased and can offer at highly discounted rates. The fare rules could require anything from absolutely no changes allowed to free changes as long as availability exists. They may or may not allow for advance seat selection or the accumulation of frequent flyer miles. If you call an airline looking for the rules to an unpublished fare you would be out of luck. They are not offered for sale by the airline online or over the phone with the airline.
Unpublished airfares are also known as private fares or consolidator fares, or, sometimes, wholesale fares. They can be up 20 to 60 percent off the regular fare. If you are working with a tour company you may be already taking advantage of this saving. Otherwise, a way to find them is to check with a travel agency. Travel agencies have special agreements with airlines. They may incorporate the savings in an over-all itinerary price as they work with you. It's worth a try to compare pricing.