Adhi Poson Full Moon Poya Day
| Date | Type |
|---|---|
30 May 2026 Saturday | BankPublicMercantile |
Overview
An "Adhi" Poya is an intercalary, or leap, full moon inserted into the Buddhist lunar calendar roughly once every three years to keep it aligned with the solar year. Since twelve lunar months add up to only about 354 days, a periodic extra month prevents the lunar calendar from steadily drifting out of sync with the seasons, similar in principle to a leap year. When this adjustment falls near the month of Poson, the additional full moon is observed with the same religious weight as any other Poya day, even though it doesn't commemorate a distinct historical event of its own the way most named Poya days do. In practice, most years have the familiar twelve Poya days; an Adhi Poya year has thirteen, and which month gets the "extra" full moon varies from one leap cycle to the next.
Significance
It doesn't mark a distinct historical event of its own; rather, it exists as a calendrical adjustment within the Buddhist lunar calendar, and is treated with the same religious observance as any other Poya day.
How it's observed
As with all Poya days, expect alcohol sales suspended nationwide. This holiday doesn't occur every year — check the current year's calendar, as it depends on the lunar cycle.
See the Sri Lanka long weekends list or use the interactive holiday planner.