The Chularatchamontri Office issued an announcement setting the first day of Ramadan as the start of fasting which falls on Thursday, 19 February 2026
On 18 February 2026, the Chularatchamontri Office announced that "the first day of the month of Ramadan in the Hijri year 1447" stating, "As announced to Thai Muslim brothers and sisters nationwide to sight the moon to determine the first day of Ramadan, Hijri year 1447, on Wednesday, 18 February 2026, after sunset, it was confirmed that the moon was sighted.
Therefore, it is hereby announced that the first day of Ramadan, Hijri year 1447, corresponds to Thursday, 19 February 2026."
Thanks to the Chularatchamontri Office Facebook page