A “stopover” is usually defined as a connection or stop that lasts for 24 hours or more for international travel and four hours or more for domestic travel (shorter connections are called layovers). Normally, passengers hate long layover flights that feel like huge time wasters. But with stopovers — and stopovers planned well — you don’t necessarily have to spend your time at the airport. You can use the downtime between transit to explore and add another adventure to your trip.

Airlines with free stopovers allow you to visit more places on the same flight ticket. Keep in mind, though, that you’ll sometimes have to pay more in airport taxes and fuel surcharges with this option.

Here are some of the best airlines for free stopovers for your next award or cash flight.

1. Japan Airlines

Mileage Bank, the Japan Airlines frequent flyer program, has one of the best stopover policies, with very liberal rules. Flyers can take advantage of complimentary stopovers when booking a JMB Partner Airline Award or Oneworld award with Japan Airline miles.

JMB Partner Airline Award

The JMB Partner Airline Award allows you to fly on any single partner airline (except Jetstar Japan) with up to three complimentary stopovers.

For example, you could fly American Airlines between New York City and Tokyo, and have three stopovers along the way. Here’s how this could look:

New York City-Miami.

Miami-Orlando.

Orlando-Los Angeles.

Los Angeles-Tokyo.

Tokyo-New York City (with a layover in Dallas).

All for the same amount of points as a more direct round-trip flight between New York City and Tokyo.

Oneworld Award

Book travel on two or more Oneworld airlines with up to seven complimentary stopovers. That’s an incredible value if you have some time on your hands.

For example, you could book the following itinerary:

Miami-Milan (American Airlines).

Milan-London (British Airways).

London-Hong Kong (Cathay Pacific).

Hong Kong-Osaka (Cathay Pacific).

Osaka-Tokyo (Japan Airlines).

Tokyo-Miami (American via Dallas).

Image courtesy of Great Circle Mapper

2. Cathay Pacific

Asia Miles allows up to five complimentary stopovers (your destination is also considered a stopover) on its Oneworld multi-carrier award. You can use three or more Oneworld airlines when one of your flights is on Cathay Pacific or two Oneworld airlines without Cathay Pacific.

In other words, you can fly and stop in up to five cities for the same number of miles it would cost you to visit Hong Kong.

Here's an example flight itinerary:

Dallas-Hong Kong (American Airlines).

Hong Kong-Bangkok (Cathay Pacific).

Bangkok-Kuala Lumpur (Malaysia Airlines).

Kuala Lumpur-Tokyo (Japan Airlines).

Tokyo-Dallas (American Airlines).

3. Alaska Airlines

Alaska Mileage Plan has a great stopover policy: You can have one complimentary stopover on a one-way flight and up to two stopovers on a round-trip. That doesn’t include the destination, so you can visit three places for the price of one.

Alaska has some very generous award charts for some of its partners, so there are a number of excellent options to use stopovers on the way to or from your destinations. You can stop in Hong Kong on the way to the Middle East or South Africa (Cathay Pacific), explore Tokyo on the way to Bangkok, or enjoy Fiji on the way to Australia.

4. ANA

You can book only a round-trip award flight with ANA, but it comes with a complimentary stopover along the way, whether you’re flying on ANA or its airline partners.

5. United Airlines

United does allow one-way award travel, but a complimentary stopover comes only with a round trip flight or a combination of three or more one-way flights. Dubbed Excursionist Perk, it has some restrictions, the most important is that its origin and destination must be within a single MileagePlus defined region.

6. Air Canada

Aeroplan doesn’t allow free stopovers anymore, but you can add up to two for 5,000 points each on a round-trip flight (or one on a one-way flight). Although it’s not free, it's more than reasonable. Even better, Aeroplan has eliminated fuel surcharges including surcharges it used to add to the partners (although it now charges a $39 fee for booking a partner’s flight).

Airlines with free stopovers, recapped

If you want to optimize your spending (and your schedule allows for it), use complimentary stopovers to see more amazing places for the same amount of miles. You’ll still have to pay more in airport taxes and carrier-imposed surcharges (if applicable), but in most cases, it will save you time, miles and money versus booking separate trips.