The highest class will include snacks, W-Fi and bags.

Free Wi-Fi? Free checked bags? Free snacks? Spirit?

The Florida-based airline, which is virtually synonymous with low-cost air travel in the United States, said Tuesday it plans to offer bundles for its most expensive tickets, wrapped in perks it used to charge for a la carte tickets. It's an attempt to boost revenue as it grapples with the fallout from a blocked U.S. takeover by JetBlueengine recalls, an oversupplied domestic market and larger rivals that have capitalized on both premium and cost-conscious travelers.

Beginning late next month, Spirit will offer four categories of service:

• “Go Big” tickets will include a spot in one of the airline's Big Front Seats, its spacious seats at the front of its Airbus planes. Rather than selling travelers just the seat, the allotment will include free Wi-Fi, a checked bag, one piece of carry-on luggage and, as CEO Ted Christie told CNBC, “unlimited” snacks and drinks, including alcoholic beverages.
• Below that package is “Go Comfy,” which will offer travelers a seat with standard legroom, but a blocked middle seat for extra space. That offer also includes early boarding, a snack, a non-alcoholic beverage, checked luggage and a carry-on bag.
• Go Savvy fares include checked or carry-on baggage.
• Then there's “Go,” essentially Spirit's original product, with just one seat and fees for checked bags, carry-on bags, seat selection, Wi-Fi and snacks.

The options will be available to book on August 16, and all four will be available on flights beginning August 27.

Spirit is competing with larger airlines like United that have capitalized on cost-conscious travelers with their own basic products but still offer pricier options like extra legroom and first class.

“What we realized now is that we were ceding other markets to other airlines,” Christie said in an interview. “Now we're saying no, we can continue to do what we were doing before, but we're also going to compete for people who are willing or want a little bit more of a premium experience and are willing to pay for it. But they didn't have that with us.”

Earlier this month, Spirit warned of a bigger-than-expected loss after non-ticket revenue (what it collects in the form of fees) came in lower than it had previously forecast. The airline also warned pilots of possible furloughs in the coming months.

Spirit isn't the only airline looking to expand its premium seating to attract more customers. Southwest AirlinesAlso under pressure to boost revenue, the airline said last week it plans to abandon open seating and offer “premium” seats with more legroom, the biggest overhaul in the airline's more than 50 years of flying. Frontier Airlines In March, it said it would begin offering blocked middle seats at the front of the plane for a higher price.