Cheap flights from Chiang Mai to Koh Samui from $73 CNX → USM
Chiang Mai International Airport (CNX) → Koh Samui Airport (USM)
The cheapest return found recently is $301 with Thai AirAsia, 19 Jan 2027 – 26 Jan 2027, found 6 days ago. The cheapest one-way found recently is $73 with Bangkok Airways, 17 Nov, found 2 days ago.
- Cheapest one-way found recently
- $73, found 2 days ago
- Cheapest return found recently
- $301, 19 Jan 2027 to 26 Jan 2027
- Usual return price
- $288 to $319
- Cheapest month to fly
- January 2027, return fares from $275 found in the last 7 days
- Airlines with nonstop flights
- Bangkok Airways
Return
The cheapest return fare on each of 3 departure dates is usually $288 to $319.
Cheapest return found recently
$301
19 Jan 2027 – 26 Jan 2027 · Thai AirAsia
Chiang Mai International Airport (CNX) → Koh Samui Airport (USM)
Leaves 12:30 p.m. · Return leaves 8:50 a.m. · 24 h 10 min of travel, both ways together
out 1 stop, back nonstop
found 6 days ago
Cheapest nonstop return
$405
13 Dec – 16 Dec · Bangkok Airways
Chiang Mai International Airport (CNX) → Koh Samui Airport (USM)
Leaves 11:30 a.m. · Return leaves 10:40 a.m. · 3 h 35 min of travel, both ways together
out nonstop, back nonstop
found 7 days ago
Found recently, and the cheapest we hold
$301 19 Jan 2027 – 26 Jan 2027found 6 days agoSee prices for these dates
$275 24 Jan 2027 – 30 Jan 2027found 7 days agoSee prices for these dates
What have prices looked like?
Over 48 days, 24 Sept to 11 Nov, the cheapest return we saw each day was $248 to $388.
Those were the prices on those days, not today's.
Is this a good return price?
Compared with the cheapest return fare on each of 3 departure dates from 13 Dec to 24 Jan 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other 7-night return fares leaving within 3 days of 19 Jan 2027 to compare.
Every date we hold
11 fares on 3 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 13 Dec – 16 Dec | $337 | Bangkok Airways | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | out 1 stop, back nonstop | found 7 days ago | See prices for these dates |
| 19 Jan 2027 – 26 Jan 2027 | $301 | Thai AirAsia | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | out 1 stop, back nonstop | found 6 days ago | See prices for these dates |
| 24 Jan 2027 – 30 Jan 2027 | $275 | Thai AirAsia | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | out 1 stop, back nonstop | found 7 days ago | See prices for these dates |
Which month looks cheapest?
January 2027 is the cheapest month — from $275.
Airlines on the cheapest dates: Thai AirAsia, Bangkok Airways.
One-way
The cheapest one-way fare on each of 6 departure dates is usually $122 to $137.
Cheapest one-way found recently
$73
17 Nov · Bangkok Airways
Chiang Mai International Airport (CNX) → Koh Samui Airport (USM)
Leaves 11:30 a.m. · 1 h 45 min trip
stops unknown
found 2 days ago
Cheapest nonstop one-way
None seen yet.
Found recently, and the cheapest we hold
$73 17 Novfound 2 days agoOpen this trip
It is also the cheapest one-way we hold, of any age.
What have prices looked like?
Over 48 days, 24 Sept to 11 Nov, the cheapest one-way we saw each day was $73 to $188.
At $73, the cheapest one-way found recently is at the low end of that range.
Those were the prices on those days, not today's.
Is this a good one-way price?
Compared with the cheapest one-way fare on each of 6 departure dates from 17 Nov to 7 Jul 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other one-way fares leaving within 3 days of 17 Nov to compare.
Every date we hold
8 fares on 6 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 17 Nov | $73 | Bangkok Airways | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | stops unknown | found 2 days ago | Open this trip |
| 10 Feb 2027 | $139 | Thai AirAsia | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | 1 stop | found 5 days ago | Open this trip |
| 16 Feb 2027 | $129 | Thai AirAsia | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | 1 stop | found 5 days ago | Open this trip |
| 18 Feb 2027 | $139 | Thai AirAsia | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | 1 stop | found 5 days ago | Open this trip |
| 11 Mar 2027 | $126 | Thai AirAsia | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | 1 stop | found 2 days ago | Open this trip |
| 7 Jul 2027 | $120 | Thai Vietjet Air | Chiang Mai International Airport (CNX) → Koh Samui Airport (USM) | 1 stop | found 3 days ago | Open this trip |
Which month looks cheapest?
November 2026 is the cheapest month — from $73.
Airlines on the cheapest dates: Thai AirAsia, Bangkok Airways, Thai Vietjet Air.
Premium cabin fares from Chiang Mai to Koh Samui
We hold no premium economy, business or first-class fares for this route: we collect them for the busiest routes, and this one is not among them yet.
Today's prices for 19 Jan 2027 – 26 Jan 2027 in another cabin: Premium economy · Business · First
Today's prices for 17 Nov in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Chiang Mai to Koh Samui?
Return
The cheapest fares were 0 to 6 days before departure.
From the cheapest return each day between 24 Sept and 11 Nov (48 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $282 | $273 | Cheapest seen | 18 |
| 7–13 days | $324 | $273 | +15% | 14 |
| 14–29 days | $324 | $248 | +15% | 35 |
| 30–59 days | $337 | $248 | +20% | 31 |
| 60–89 days | $337 | $249 | +20% | 35 |
| 90–179 days | $299 | $256 | +6% | 20 |
| 180+ days | $320 | $320 | +14% | 8 |
One-way
The cheapest fares were 0 to 6 days before departure.
From the cheapest one-way each day between 24 Sept and 11 Nov (48 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $105 | $73 | Cheapest seen | 16 |
| 90–179 days | $135 | $126 | +29% | 39 |
| 180+ days | $134 | $111 | +28% | 35 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
One-way
Chiang Mai → Surat Thani
94 km from Koh Samui
$66
$7 less than flying to Koh Samui
15 Jun 2027 · CNX → URT · 1 stop
found 2 days ago
Cheapest recent price on each route — one way, per traveler in Economy. Distances are in a straight line.
Live price for these dates
The cheapest return found recently is for 19 Jan 2027 – 26 Jan 2027. A live search on this page shows what those dates cost now, for one adult in economy.
Questions about this trip
How much is a return flight from Chiang Mai to Koh Samui?
The cheapest return found recently is $301 with Thai AirAsia, 19 Jan 2027 to 26 Jan 2027, found 6 days ago. The cheapest return we hold, of any age, is $275 with Thai AirAsia, 24 Jan 2027 to 30 Jan 2027, found 7 days ago. The cheapest return fare on each of 3 departure dates is usually $288 to $319.
How much is a one-way flight from Chiang Mai to Koh Samui?
The cheapest one-way found recently is $73 with Bangkok Airways, 17 Nov, found 2 days ago. The cheapest one-way fare on each of 6 departure dates is usually $122 to $137.
What is the cheapest month to fly from Chiang Mai to Koh Samui?
January 2027 is the cheapest month for a return, from $275, 24 Jan 2027 to 30 Jan 2027, found 7 days ago. November 2026 is the cheapest month for a one-way, from $73, 17 Nov, found 2 days ago.
How far ahead should I book a flight from Chiang Mai to Koh Samui?
In 48 days of prices between 24 Sept and 11 Nov, return and one-way fares were both cheapest 0 to 6 days before departure.
Is there a direct flight from Chiang Mai to Koh Samui?
Yes, the cheapest nonstop return found recently is $405 with Bangkok Airways, 13 Dec to 16 Dec, found 7 days ago.
Which airlines have the cheapest flights from Chiang Mai to Koh Samui?
Between 13 Dec and 24 Jan 2027, Thai AirAsia has the cheapest return on 2 of the 3 departure dates we hold, and Bangkok Airways on 1. Between 17 Nov and 7 Jul 2027, Thai AirAsia has the cheapest one-way on 4 of the 6 departure dates we hold, Bangkok Airways on 1 and Thai Vietjet Air on 1.
Prices are what travelers' searches on Aviasales found in the last 7 days, in US dollars: the price the seller showed on Aviasales; bags may cost extra. Fares change, so check today's price before you book. How our prices work