The cheapest times to fly from IAH to USM are

  • February 26th to May 27th (except the week of March 5th)
  • June 11th to July 15th (except the week of June 25th)
  • August 6th to September 2nd
  • October 1st to November 25th (except the week of November 5th)

based on data collected exclusively by Champion Traveler across tens of millions of flights. Among all the dates above, the very cheapest time to fly from IAH to USM is mid April. Prices can be as high as $5831 for Thursday flights during late December, or as low as $963 for Wednesday flights around mid April.


When to Fly to Ko Samui

Flying from Houston, TX (IAH) to Koh Samui (USM) will usually cost between $975 to $4110 per person if booking more than four weeks in advance. On average the very cheapest time to fly is mid April with an average ticket price of $1002. Due to high demand the most expensive time to fly is late December, with an average price of $3736. Planning your trip to low-cost times can easily save you $2734 on economy flights and even more on first-class flights. Generally, any price below $1150 can be considered a good price for a round-trip IAH to USM flight.

See below for a graph of average weekly prices for the IAH to USM route. All prices are for round-trip tickets in USD.

IAH to USM Flight Prices

Compared to other flights, the IAH to USM flight is slightly more expensive than the average and costs about as much as the average flight leaving from Houston. The average price per mile (for a direct flight) is $0.08, which is far below average.


Flight Prices by Day of the Week

Wednesday is usually the cheapest day to fly to USM, and Sunday the cheapest day to fly back into IAH. Thursdays are the most expensive days to fly to Ko Samui, and Tuesdays are the most expensive days to return to Houston. Selecting flights on the least expensive days could save you up to $665 (30%) on this flight.

Departing prices are for round-trip flights returning on the day of departure. For example, a flight departing on Wednesday and returning a week later will cost an average of $1171. Return trip prices are from the USM to IAH flight, and often highlight the quality of our data in showing the same trend.

Departing Prices by Day

Departure Day Prices

Return Trip Prices by Day

Return Day Prices


Nonstop Flights and Layovers

Travelers looking to fly from IAH to USM can generally find a 2-layover flight. Because there is not usually a direct flight option the real-world direct flight time of 18 hour 7 minutes may not be realistic.


Flight Hacking IAH to USM

Flight hacking is when you book two tickets instead of a layover, sometimes with different airlines. You will need to either bring only a carry-on bag (highly recommended) or leave yourself plenty of time to go through security again. Flight hacking is completely allowed, but airlines don’t always tell you the cheapest way to get from IAH to USM — but Champion Traveler does!

Hack #1: Bangkok (IAH > BKK > USM)

  • Price for both tickets: $969
  • Average savings: $182 (15.78%)

See IAH to BKK flights

Hack #2: Chiang Mai (IAH > CNX > USM)

  • Price for both tickets: $1124
  • Average savings: $27 (2.3%)

See IAH to CNX flights

Hack #3: Singapore (IAH > SIN > USM)

  • Price for both tickets: $1124
  • Average savings: $27 (2.3%)

See IAH to SIN flights


Flight Questions Answered

Still have questions about flying from IAH to USM? We’ve got answers.

Which airlines fly this route?

You can find 15 major airlines flying this route most often: Air France, Austrian, Bangkok Airways, British Airways, Cathay Pacific, Emirates, EVA Air, Finnair, JAL, KLM, Malaysia Airlines, Qatar Airways, Singapore Airlines, THAI, Turkish Airlines, and potentially more during busy seasons.

How far away is it from Samui Airport to George Bush Intercontinental/Houston Airport?

The distance between the two airports is roughly 9518 miles or 15318 kilometers.

How long does it take to fly from IAH to USM?

The real-world flight time for a nonstop IAH to USM flight is about 18 hour 7 minutes.

How many flights go between Houston, TX and Koh Samui?

It depends on the day of the week and the date, but a typical day might have around 9 available flights from IAH to USM.


Airport Location Info


Departing Airport

Origination code IAH
Origination airport name George Bush Intercontinental/Houston Airport
City Houston, TX
Country the United States
Latitude 30
Longitude -95.3

Return Airport

Destination code USM
Destination airport name Samui Airport
City Koh Samui
Country Thailand
Latitude 9.5
Longitude 100.1


Other Resources

Please note that while we’ve worked hard to analyzed tens of millions of flights to get you this data, we do not calculate current live prices or guarantee pricing. Please see our partners using the links above for current offers.