Whether you prefer to fly on a legacy carrier or are able to go bare bones and fly an ultra-low-cost carrier, we've got some great airfares on all airlines to tell you about today. Here's a look at the top 10 airfares we've found so far today.

Today's Top Airfare Picks

There are many sales going on this week. Along with the advertised sales, there are plenty of unadvertised deals popping up. If you are interested in any of these fares, we recommend you book soon to avoid a missed bargain. All domestic flights also work in the reverse direction.

Milwaukee - San Diego $43 Roundtrip for Fall Travel

Frontier is having one of its best promo code sales of the year. Take up to 90% off your next Frontier flight for fall travel. Don't hesitate on this one as this promo code sale ends tonight. One of the best deals from this sale is nonstop service from Milwaukee to San Diego for $43 roundtrip. Using the promo code SAVE90 on FlyFrontier.com, I found seats departing Milwaukee MKE on Thursday, September 6, returning from San Diego SAN on Thursday, September 13. This super low fare only includes one small personal item. Checked bag fees start at $25 each way. Larger carry-on bag fees start at $30 each way. If you want to know more about this ultra-low-cost carrier, check out our guide on Everything You Need to Know Before You Fly Frontier.

See all of our fares to San Diego (SAN) from all over the US and Canada

Las Vegas - San Francisco $98 Roundtrip for Fall/Winter Travel

From the ongoing Southwest sale, flights from Las Vegas to San Francisco are just $98 roundtrip. In this direction, peak weekend travel dates are available. Travel from Las Vegas Tuesdays through Fridays. Return from San Francisco Sundays through Wednesdays. For example, I found seats departing Las Vegas LAS on Friday, September 14, returning from San Francisco SFO on Sunday, September 17. You'll find other travel dates available through mid-February. United and Alaska are matching this sale fare, but Southwest offers two free checked bags and no change fees. For more of Southwest's perks, check out our guide on How to Fly Southwest Airlines (And Get the Seat You Want).

See all of our fares to San Francisco (SFO) from all over the US and Canada

St. Louis - Portland $154 Roundtrip for Fall/Winter Travel

Here's a big price drop on United. Fly from St. Louis to Portland, Oregon for $154 roundtrip. Travel is valid on scattered Tuesdays, Wednesdays, Thursdays, and Saturdays, through mid-February. December holiday travel is blacked out. I found seats departing St. Louis STL on Saturday, September 15, returning from Portland PDX on Thursday, September 20. This is a Basic Economy fare, which only includes a small personal item. If you need to bring more luggage, it will be cheapest to pay $25 each way for a checked bag on the Basic Economy fare. Upgrading to a standard Economy fare will cost an additional $100 and includes a normal carry-on bag plus a personal item and standard seat selection.

See all of our fares to Portland (PDX) from all over the US and Canada

Denver - San Juan $236 Roundtrip for Fall Travel

Looking to descend from the mile high city all the way down to the Caribbean? Delta has a great fare from Denver to San Juan for $236 roundtrip. No passport required. Travel is valid on a few select Mondays, Tuesdays, Wednesdays, and Thursdays, in late September and October. I found seats departing Denver DEN on Wednesday, September 19, returning from San Juan on Wednesday, September 26.

See all of our fares to San Juan (SJU) from all over the US and Canada

Boston - Mexico City $247 Roundtrip for Year-Round Travel

JetBlue is starting new nonstop service to Mexico this fall. With the added competition, Aeromexico has had to drastically drop its fares. Now you can fly on either airline from Boston to Mexico City for $247 roundtrip. Travel is widely available throughout the year, except for peak holiday travel. I found seats departing Boston BOS on Friday, November 23, returning from Mexico City MEX on Friday, November 30. This is a Basic fare on Aeromexico, which doesn't allow for seat selection, but it includes a normal carry-on baggage allowance just like JetBlue. Checked bag fees on JetBlue are now $30 each way. Aeromexico's checked bag fees start at $25 each way.

See all of our fares to Mexico City (MEX) from all over the US and Canada

Washington D.C. - San Salvador $262 Roundtrip for Fall/Winter Travel

Low-cost Mexican airline Volaris is having one of its better promo code sales of the year. Take up to 70% off flights through March if you purchase by 11:59 pm CT, tonight. One of the bigger price drops from this sale is the relatively new nonstop route from Washington D.C. to San Salvador for $262 roundtrip. By selecting the promo code on Volaris.com, I found seats departing Washington-Dulles IAD on Sunday, February 10, returning from San Salvador SAL on Monday, February 18. Volaris clean base fares include a total of 22 lbs. in two standard sized carry-on bags. You can add extra weight or check a bag for a small fee.

See all of our fares to San Salvador (SAL) from all over the US and Canada

Los Angeles - Honolulu $299 Roundtrip for Fall Travel

There have been some amazing price drops to Hawaii lately. Our most popular route rarely dips this low. Fly from Los Angeles to Honolulu for $299 roundtrip on American, Delta, Hawaiian, or United. Travel is widely available through September, with no advance purchase required. You can still leave tonight or take off for a last-minute Labor Day Weekend trip. I found seats departing Los Angeles LAX tomorrow, Thursday, August 30, returning from Honolulu HNL on Monday, September 3.

See all of our fares to Honolulu (HNL) from all over the US and Canada

Fort Lauderdale - Oslo $318 Roundtrip for Fall/Winter Travel

Norwegian Air is having a sale on all routes for purchase through September 5. One excellent deal from this sale is nonstop service from Fort Lauderdale to Oslo for $318 roundtrip. Travel is valid on Mondays, Wednesdays, and Fridays, from late October through March. I found seats over Thanksgiving break, departing Fort Lauderdale FLL on Wednesday, November 21, returning from Oslo OSL on Wednesday, November 28. Norwegian's LowFare only includes 10 kg (22 lbs.) of hand luggage. Checked bag fees start at $45 each way.

See all of our fares to Oslo (OSL) from all over the US and Canada

New York - Valencia $431 Roundtrip for Year-Round Travel 

One of the most affordable ways to get to Europe is by booking a cheap flight to Spain. Delta's partner Air Europa has great deals all over Spain including New York to Valencia for $431 roundtrip. Travel is valid on scattered dates throughout the year. I found seats departing New York JFK on Monday, April 22, returning from Valencia VLC on Monday, April 29. This Lite fare only includes carry-on luggage. A standard Economy fare is $512 roundtrip if you need to check bags.

See all of our fares to Valencia (VLC) from all over the US and Canada

Chicago - Warsaw $549 Roundtrip for Fall/Winter/Spring Travel

Craving some Pierogies? Fly from Chicago to Warsaw for $549 roundtrip on SAS. Travel is valid almost daily from November through early June. A Saturday night stay is required.  No outbound travel on Fridays and no inbound travel on Sundays. As an example, I found seats departing Chicago ORD on Saturday, November 10, returning from Warsaw WAW on Saturday, November 17.

See all of our fares to Warsaw (WAW) from all over the US and Canada

Header image by Yuganov Konstantin via Shutterstock.

All products and services mentioned on Airfarewatchdog are independently selected by our team of expert travelers. If you buy something through our links, we may earn an affiliate commission.

More Stories You'll Love