In an attempt to compete on a level playing field with upstart ultra-low-cost airlines Allegiant, Frontier, and Spirit, three of the four remaining “legacy” airlines (American, Delta, and United) have begun selling less expensive “basic economy” airfares. So now you’ll have as many as five airfare products to choose from on some flights: first, business, premium economy, regular economy,and basic economy. The two most important features of basic economy to note: on some airlines, you’re not allowed to place a bag in the overhead bins (whatever you carry on board must be small enough to fit safely under the seat in front of you); and because you can’t choose a seat in advance, you’ll be assigned a middle seat at check in or at the gate, probably at the back of the plane. But there are other restrictions and rules to note, which I’ve broken down by airline, and there are subtle differences between airlines (for example, Delta customers earn full frequent flier accruals and can use overhead bin space, but not those on American and United).

Southwest, Alaska, JetBlue, Virgin, and most foreign-based airlines haven’t introduced this new fare class. And while Frontier and Allegiant still allow changes and cancellations for a fee, American, Delta and United do not. When buying these fares, note that on shorter routes, the price difference between basic economy and regular economy may not be worth the perks you surrender, so choose carefully.

Allegiant

What it’s called: Economy class

Maximum carry-on bag size: 9 x 14 x 22 in. (22.9 x 35.6 x 55.9 cm)

Overhead bin use? Allowed for $15-$20 fee each way if paid for at time of booking flight (up to $50 if paid at airport)

Advanced seat selection: $0 to $80

Upgrade eligible? Not applicable

Fee for changes/cancels? $75 (no refund for changes/cancels within 7 days of departure)

Boarding priority: allowed for $4 to $12

Exemptions: none

Award miles and elite qualification: not applicable

American

What it’s called: Basic economy

Maximum carry-on bag size: 18 x 14 x 8 in. (45 x 35 x 20 cm) must fit under seat in front of you (larger items brought to gate incur checked bag fee plus $25 service fee)

Overhead bin use? not allowed (see exemptions)

Advanced seat selection: You can choose a specific seat within 48 hours of departure, but a fee will apply. Otherwise, seats will be automatically assigned for free when you check in; however if you enter your children’s age in the reservation they will try to seat those aged 13 and under with parents.

Upgrade eligible? No

Fee for changes/cancels? No changes or cancellations unless made  both within 24 hours of purchase and 7 days ahead of travel

Boarding priority: last to board

Exemptions: AAdvantage members with elite status and AA credit card holders keep all boarding and overhead bin privileges

Award miles and elite qualification: Elite Qualifying Miles (EQMs) and Elite Qualifying Segments (EQSs) earned at a reduced rate of 0.5 per mile/flight segment flown regardless of frequent flier status

Delta

What it’s called: Basic economy

Maximum carry-on bag size: 22 x 14 x 9 in. (56 x 35 x  23 cm)

Overhead bin use? Allowed

Advanced seat selection: after check in or at gate only

Upgrade eligible? No

Fee for changes/cancels? No changes or cancellations unless made  both within 24 hours of purchase and 7 days ahead of travel

Boarding priority: None, even if you have frequent flier status

Exemptions: None

Award miles and elite qualification: All SkyMiles members are eligible for mileage accrual and will earn Medallion Qualification Miles (MQMs), Medallion Qualification Segments (MQSs) and Medallion Qualification Dollars (MQDs – U.S.-based members only) on Basic Economy fares.

Frontier

What it’s called: Economy class

Maximum Carry-on bag size: 24 x 16 x 10 in. (but under 35 lb.)

Carry-on bag fee: $30-$35 each way if paid for on FlyFrontier.com at booking and up to 24 hours before flight ($60 at departure gate)

Overhead bin use? Allowed, upon payment of a carry-on bag fee

Advanced seat selection: Allowed for $6 via Flyfrontier.com, at booking and up to 24 hours before departure or free at check in or at gate

Upgrade eligible? No

Fee for changes/cancels? $99 ($75 to change the name of a passenger)

Boarding priority: None

Exemptions: None

Award miles and elite qualification: standard and/or not applicable

Spirit

What it’s called: Bare Fare

Maximum Carry-on bag size: Free bag must measure 16 x 14 x 12 in. (40 x 35 x 30 cm) including handles and wheels, must fit under seat; paid carry-on size is 22 x 18 x10 in. (56 x 46 x 25 cm)

Overhead bin use? Allowed, for the above fee

Advanced seat selection: $1 to $50

Upgrade eligible? Yes (to “Big Front Seat” for $25-$75 per flight segment)

Fee for changes/cancels? Not allowed (unless made within 24 hours of booking and 7 days ahead of travel).

Boarding priority: Not applicable

Exemptions: None

Award miles and elite qualification: Standard and/or not applicable

United

What it’s called: Basic economy

Maximum Carry-on bag size: 9 x 10 x 17 in. (22 cm x 25 cm x 43 cm) must fit under seat

Overhead bin use? Not allowed. Everyone else who brings a full-sized carry-on bag to the gate will be required to check their bag and pay the applicable checked bag fee plus a $25 gate handling charge.

Advanced seat selection: Not allowed. Assigned at boarding. There is no accommodation for families traveling together.

Upgrade eligible? No

Fee for changes/cancels? Not allowed (unless made within 24 hours of booking and 7 days ahead of travel).

Boarding priority: No

Exemptions: MileagePlus Premier member or companion traveling on the same reservation, the primary cardmember of a qualifying MileagePlus credit card or a Star Alliance™ Gold member may use overhead bins.

Award miles and elite qualification: these fares do not earn Premier qualifying dollars (PQD), Premier qualifying miles (PQM), Premier qualifying segments (PQS), Lifetime miles
or credit toward the four-segment minimum.