As coach travel gets more cramped, airlines have added “premium economy” sections that promise more space and comfort-often at a substantially higher cost.

Air carriers have found that many travelers are willing to pay two or even three times the prevailing economy fare to avoid crowded bus limits. The extra money is mostly profit for airlines, which is why so many now offer this class of service.

But what you get can vary greatly depending on the airline. A little buyer beware knowledge the next time you plan a trip can help you avoid spending money on upgrades that aren’t worth it.

MORE SPACE, BUT NOT NECESSARILY MORE COMFORT

Premium economy big selling point more space. The seats are an inch or two wider on average than a typical bus seat, and the rows are further apart, offering a few more inches of legroom. Most premium economy seats recline, and many have footrests.

How much space you actually get depends on the airline. According to SeatGuru’s seat review website, Japan Airlines offers about 10 inches more legroom than you would normally find on a bus, while most other carriers offer only 5 or 6 inches more.

And not all seats are equally comfortable. Many reviewers dislike the “fixed shell” design used by Air France and Aeroflot t, where the seat slides forward rather than reclines.

What the premium economy doesn’t offer: reclining-flat beds that are now the standard for long-haul business and first-class cabins. Again, fares on these flights are usually thousands of dollars more than you would pay for a premium economy.

WHAT ABOUT EXTRA?

The amenities and customer service you get in premium economy are all over the map. Some, including premium economy pioneer Virgin Atlantic, offer priority check-in counters, warm seats, convenience kits, plenty of good quality food and expedited baggage handling. Others, such as discount carrier Norwegian Air, save on extras by offering less to their premium economy customers than other airlines provide on the bus.

For example: Free snacks and meals are fairly standard on international flights, even in economy-on-ice. Norwegian, however, does not offer free meals other than small meals served in boxes for premium economy passengers. The carrier has also lowered the weight limit for free checked bags from the industry standard of 23kg (50lb) to just 20kg (44lb) and sets a weight limit on carry-on Luggage (10kg, or 22lb). Its check-in counters do a brisk business in charging extra fees for those unable to read the small print.

SeatGuru can give you some idea of the space you can expect, and the airline’s website usually details what’s included in the fare. Don’t rely too much on travel site reviews as they may be outdated and airline policies may change.

DO YOU PAY MORE FOR LESS?

The airfare you pay doesn’t necessarily reflect what you get. For example, for an April trip from Los Angeles to London, Kayak shows a $ 1,698 premium economy fare for Virgin Atlantic versus $ 1,747 charged Norwegian. (Air New Zealand, winner of the 2019 TripAdvisor Travelers ‘ Choice Awards for best premium economy, charges $1,612.)

Lowest economy fares on the same route: $638 for Virgin Atlantic, $556 for Norwegian and $576 for Air New Zealand. This means that the premium you would pay for a premium economy-the amount above the airline’s economy fare – is significantly higher for Norwegians than for the other two carriers.

(For reference, business class fares on the same route start at $ 3033 for Virgin Atlantic and $ 2842 for Air New Zealand. Norwegian does not have business class.)

The gap between economy and premium fares tends to narrow as the travel date approaches, airline experts say. If you book your ticket within three months of departure, for example, you can only pay a few hundred dollars more to get a premium economy, which can be a good deal.

Airlines can also give you the option to upgrade – again, for a few hundred dollars and sometimes less – when you check in, if all of the economy’s premium seats haven’t been sold.

Paying the full price for a premium economy may make sense in some circumstances. Enduring five or more hours in a cramped coach seat can be difficult for older or taller travelers. A good premium economy cabin can also boost special occasions like a honeymoon, or a business trip where you need to arrive in pretty good shape. You just need to do some research to make sure that what you get will be worth the extra money.

This column was provided by the Associated Press on the personal Finance website NerdWallet. Liz Weston is a nerdwallet columnist, certified financial planner and author of ” Your credit score.” Email: [email protected]. Twitter: @lizweston.

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