Frontier Airlines debuted a few changes to their policies today and guess what? They’re charging for more things, including carry-on bags and formerly complimentary in-air beverages. Here’s the deal, as we understand it: Travelers who book their reservations through the airline’s site won’t have to pay a dime for a carry-on bag, but those who use booking sites like Orbitz or Expedia will have to pay. As for exactly how much, that’s where it gets confusing.

According to a press release from Frontier, customers who book “Economy” tickets through FlyFrontier.com can enjoy the same old free carry-on policy of one carry-on and one personal item. Should you choose a third-party service to reserve your “Basic” ticket, you’ll be charged  “$25-100 (customers enjoy the lowest price by checking in at FlyFrontier.com).”

From that, we gather that if you book through another site, but then check in on Frontier’s site, you’ll pay $25 for a carry-on. Fine, that’s clear. But since there’s a range of fees, we wanted to know under which circumstances you’d pay more; say $50, $75 or $100. So we got in touch with Frontier and asked that question, a few times.

Via email, we received responses like ” Customers who book Basic fares on OTA’s and other sites will be charged between $25 and $100 based on where they check in. Customers can enjoy the lowest price by checking in online at FlyFrontier.com.”

When we asked for more clarification on the when/where part and how customers will know whether they’ll be charged $100, for example, the reply was heavy on the airline industry spin and light on actual details or facts:  “It’s all about cost savings. Checking in online saves the airline overhead costs. Customers will receive messaging when they make their reservations notifying them of the check-in choices and associated costs.”

Consumerist has asked for a more complete explanation of that range of fees — an actual breakdown of check-in options and corresponding prices — and we’ll let you know if we ever get a response containing actual information that is of use to Frontier customers.

As for other changes — soda, juice, tea and coffee? Not free anymore. Those beverages will cost travelers $1.99.

It’s also worth noting that as of July 1, customers who book their tickets on third-party sites will only earn somewhere between 25% and 50% of the miles they fly, while reserving with Frontier directly will earn fliers the usual 100%, 125% and 150% accrual rate.

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