If you are looking to fly to the Middle East or Asia there are sales for 6 days on Emirates for the dates of August 22nd to December 6th. You can fly to places like Delhi for $819 round trip from Houston.   https://www.emirates.com/us/english/book/featured-fares/?utm_medium=email-pr&utm_source=ek&utm_campaign=SFMC_us_en_winterearlybird_31072018_in&utm_term=eb_na_xx_xx_xx_xx_xx&utm_content=CCDESTPUSH_east_heroCTA-booknow&utm_pid=25374512&utm_mid=xx  

You can get pretty good deals on flights from 8/14/2018 to 10/3/2018. if you book by 8/1/2018 on Frontier. Flights out of Houston are $49 to Denver and Raleigh-Durham. https://www.flyfrontier.com/deals/flight-sales/  

If you would like to visit Ireland or somewhere else in Europe in the fall there are great deals available as low as $390 round trip to Dublin (a steal for going to Europe). Check the fares though since some fares do not include bags or seat assignments but its still a great deal over to Europe. https://www.aerlingus.com/plan-and-book/latest-offers/flights-from-usa/flights-from-usa-to-ireland/#/tab-0-fall-fares  

Southwest is running deals on flights from August 21st to December 19th that runs until July 20th. They looks to be decent deals so check them out!   https://www.southwest.com/html/promotions/nationwide_sale_180709_offers.html?clk=1834270

Some good tips when buying tickets from airlines such Southwest, Spirit and Jet Blue.   https://finance.yahoo.com/news/8-money-saving-travel-hacks-southwest-spirit-jetblue-170159127.html  

Southwest airlines is running another sale if you purchase by April 19th, 2018 and you fly between  4/24/18 – 6/13/18 and 8/21/18 – 10/31/18. Out of Houston it looks like the cheapest fare is to Corpus Christi at $49 one way but there are some other decent fares. Click below for the deals page. Southwest Airlines deals 

If you are wanting to go to Europe Aer Lingus has summer sales for airfare to places like Dublin for as little as $619 round trip (there are restrictions involved. You can also do a stopover for free in Dublin during your trip. You will need to book by April 4th at 7pm ET to get this deal. Aer Lingus is the national airline of Ireland and it is a good airline to fly. https://www.aerlingus.com/html/en-US/home.html

If you purchase by April 2nd you can get fares as low as $20 one way on Frontier if you fly on a Tuesday or Wednesday. From Houston it looks like the fares are around $30-35 one way to Philadelphia and Raleigh-Durham. https://www.flyfrontier.com/ways-to-save/online-deals/  

If you purchase by 3/28/2018 and fly by 5/16/2018 you can get airfare as low as $29 one way. In the Houston area it looks like the specials are for Raleigh-Durham and Philadelphia. Markets like Austin have more deals available. https://www.flyfrontier.com/ways-to-save/online-deals/

If you buy by 3/26/2018 you can get some great airfare from Frontier for select dates and destinations. Its for flights between 4/9/2018 – 5/9/2018 on certain days of the week. You can get for example as low as $20 from Houston to Raleigh/Durham, NC or Philadelphia, PA one way. https://www.flyfrontier.com/ways-to-save/online-deals/