Checked bag changes: Frontier cuts allowance, Delta tests free luggage

The next time you check a bag on Frontier or Delta, you may be surprised.

With Denver-based Frontier, you may be on the hook for an overweight fee, even if you thought your bag was under the "standard" 50-pound limit.

That's because the ultra-low-cost carrier is tweaking its definition of an overweight bag, as first reported by the USA Today. Beginning on March 1, 2022, checked bags will be capped at 40 pounds each, and those that weigh between 41 and 50 pounds will be charged an additional $50 per bag, per direction.

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Bags weighing 51 to 100 pounds will be charged $100 per bag, per direction, representing a $25 increase from the previous fee for overweight bags.

Frontier's 50-pound limit will continue to apply for travel completed before March 1, 2022, as well as for all tickets purchased before Jan. 18, 2022. Everyone else will need to either pack less or pay up.

Note that the new fee structure is in addition to the charges for bringing a checked bag. You can take a look at the airline's checked-bag fee calculator on its website.

Interestingly, Frontier's move brings its policy in line with its budget carrier competitors. Both Allegiant and Spirit start charging for overweight bags beginning at 40 pounds.

While Frontier is getting stricter about checked bags, Delta Air Lines is doing the opposite.

The Atlanta-based carrier is piloting a new project that allows passengers departing from its Boston (BOS) hub to check their carry-on bags for free. Eligible flyers will receive a text message from Delta on the day of departure with a proactive offer to check their carry-on bags, an airline spokesperson confirmed to Thrifty Traveler, which first reported the news.

Related: How to avoid checked baggage fees on major domestic airlines

Delta's pilot program is limited to Boston and will last a month, after which the airline may expand the trial elsewhere.

For Delta, the move is designed to speed up the boarding process, where full overhead bins create bottlenecks that ultimately lead to delays.

While Delta will encourage flyers to check their carry-on bags, the airline will continue to keep its fee structure for checked bags. For most domestic flights, Delta charges $30 for the first checked bag and $40 for the second, both of which must be under 50 pounds to avoid an overweight fee.

Of course, if tweaked checked bag policies bother you, there's always Southwest Airlines, which continues to offer two free standard-size checked bags for each passenger, on every fare and every route across its network.