| New Year's Day (Observed) | Monday, January 2 | Celebrates the start of the solar and Gregorian year. [January 1] |
| March 2023 | | |
| Magha Puja | Monday, March 6 | Buddhist observance commemorating the Buddha's teaching of Ovada Patimokkha. [Full moon day of the third lunar month] |
| April 2023 | | |
| Chakri Memorial Day | Thursday, April 6 | Commemorates the establishment of the Chakri Dynasty and the founding of Bangkok by King Phutthayotfa Chulalok in 1782. Officially known as King Phutthayotfa Chulalok the Great Day and Chakri Dynasty Memorial Day. [April 6] |
| Songkran Festival | Thursday, April 13 – Monday, April 17 | Traditional Thai new year. The first day is known as Wan Maha Songkran, the second as Wan Nao, and the third as Wan Thaloeng Sok. [April 13 – 15] |
| May 2023 | | |
| Coronation Day | Thursday, May 4 | Commemorates the coronation of King Maha Vajiralongkorn in 2019. [May 4] |
| Additional Holiday | Friday, May 5 | Announcement of the additional holidays by Thai government |
| Royal Ploughing Ceremony | Wednesday, May 17 | Ceremony giving blessing to the country's farmers. |
| Science Seminar | Thursday, May 25 – 27 | Faculty of Science Annual Seminar |
| June 2023 | | |
| H.M. Queen Suthida Bajrasudhabimalalakshana's Birthday (Observed) | Monday, June 5 | Commemorates the birth of Queen Suthida in 1978. [June 3] |
| Vesak (Observed) | Monday, June 5 | Buddhist observance commemorating the birth, enlightenment and passing of the Buddha. [Full moon day of the sixth lunar month] |
| July 2023 | | |
| H.M. King Maha Vajiralongkorn Phra Vajiraklaochaoyuhua's Birthday | Friday, July 28 | Commemorates the birth of King Maha Vajiralongkorn in 1952. [July 28] |
| August 2023 | | |
| Asalha Puja | Tuesday, August 1 | Buddhist observance commemorating the Buddha's first discourse, the Dhammacakkappavattana Sutta. [Full moon day of the eighth lunar month] |
| Beginning of Vassa | Wednesday, August 2 | Buddhist observance marking the beginning of Vassa, also known as Buddhist Lent. [First day of the waning moon of the eighth lunar month] |
| The Queen Mother's Birthday (Observed) | Monday, August 14 | Commemorates the birth of Queen Mother Sirikit in 1932; also observed as National Mother's Day. [August 12] |
| October 2023 | | |
| King Bhumibol Adulyadej Memorial Day | Friday, October 13 | Commemorates the passing of King Bhumibol Adulyadej in 2016. [October 13] |
| King Chulalongkorn Day | Monday, October 23 | Commemorates the passing of King Chulalongkorn in 1910. [October 23] |
| December 2023 | | |
| King Bhumibol Adulyadej's Birthday | Tuesday, December 5 | Commemorates the birth of King Bhumibol Adulyadej in 1927. Also observed as National Day and National Father's Day. [December 5] |
| Constitution Day (Observed) | Monday, December 10 | Commemorates the promulgation of the first permanent constitution in 1932. [December 10] |
