Release a lantern at the festival that invented the image
24 and 25 November 2026
Yi Peng falls on the full moon of the second month of the Lanna lunar calendar, which in 2026 is 24 and 25 November, peaking on the night of the 25th. It runs across the city and along the Ping river.
Why it's unique
The name is Lanna, not Thai: yi is two and peng is the full moon day, so the second full moon of their own calendar. Northern Thailand was an independent kingdom for most of its history and kept its own calendar, and this festival belongs to that calendar rather than to Bangkok's.
It is the origin of the mass sky lantern image that now stands in for Thailand generally. Here it is a religious act with a specific meaning, releasing the year's misfortune, and it happens in the place it came from.
Before you go
There are two different things sharing a name, and the difference costs money. The enormous synchronised releases you have seen photographed are ticketed private events held outside the city, sold months ahead. The citywide festival along the Ping river and around Tha Phae Gate is free, and is the actual tradition.
It overlaps Loy Krathong, which is the same weekend and is the water version: you float a banana-leaf raft instead of sending up a lantern. Residents do both. Doing only the sky lanterns is doing half of it.
Book accommodation months out. This is the busiest weekend of the Chiang Mai year and prices roughly double.