The latest promo code sale on Frontier allows you to take up to 75% off the base fare for late summer/fall travel. Fares start at just $37 roundtrip.

Use promo code AUTUMN when booking on to take 75% off the base fare for nonstop domestic flights on Tuesdays and Wednesdays, from August 14 through October 3. Travel on Mondays, Thursdays, and Saturdays will be discounted 50% off the base fare within these dates. Avoid blackout dates between August 31 and September 3.

The discount does not apply to taxes nor Frontier's online booking fee, which is labeled a "Carrier Interface Charge". This means some routes still won't have a very big price drop even with the big sticker shock of 75% off. However, there are plenty of routes where we are seeing deep discounts.

There are many routes excluded from this sale entirely or have certain days of the week excluded. You may have to click around to find available dates since Frontier operates about half of the route network on just a few days each week. Click on the fare details for more info on exact dates each route is available.

Tickets must be booked by 11:59pm ET, on August 8, 2018.

A sample of nonstop fares include:

Atlanta to Orlando $37 roundtrip

Orlando to Raleigh $37 roundtrip

Sacramento to Las Vegas $45 roundtrip

Indianapolis to Orlando $51 roundtrip

Austin to Tampa $51 roundtrip

Denver to Salt Lake City $53 roundtrip

Charlotte to Philadelphia $68 roundtrip

Detroit to Raleigh $69 roundtrip

Cincinnati to Tampa $69 roundtrip

Milwaukee to Austin $69 roundtrip

Chicago to Denver $73 roundtrip

Memphis to Las Vegas $74 roundtrip

Harrisburg to Orlando $77 roundtrip

St. Louis to Denver $77 roundtrip

Denver to San Francisco $77 roundtrip

Denver to Santa Ana $79 roundtrip

Austin to Seattle $81 roundtrip

Portland, ME to Orlando $82 roundtrip

Cleveland to San Diego $82 roundtrip

Pittsburgh to San Diego $82 roundtrip

Atlanta to Denver $84 roundtrip

Denver to Washington D.C. $85 roundtrip

Denver to Nashville $87 roundtrip

Cleveland to Las Vegas $92 roundtrip

Atlanta to Los Angeles $94 roundtrip

Orlando to Las Vegas $98 roundtrip

Norfolk to Las Vegas $99 roundtrip

Atlanta to San Juan $106 roundtrip

Philadelphia to San Juan $121 roundtrip

Cincinnati to Los Angeles $132 roundtrip

Many more routes are available and these fares all work in reverse as well. Lowest fares may not be available throughout the entire travel period. You'll have to decline all extras to get the lowest price.

Keep in mind that Frontier charges extra for any bags larger than a small personal item (small backpack, large purse, etc.). Pack super light to get the lowest price. Checked bag fees start at $25 each way. Larger carry-on bag fees start at $30 each way.

Above image by Colin A. Pierce via Shutterstock.

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