If the old Thai Baht (BHT) banknotes in your drawer are of Series 15 (Type 2), 16 or 17, congratulations! Your Bahts are still accepted and are in circulation in Thailand.
Update: We just verified and all Series 15, Series 16 and Series Thai Baht are still accepted in 2021!
Series 15 (Type 2) Thai Baht Banknotes
Series 15 (Type 2) is the oldest Thai Baht in circulation in Thailand. This series is still widely seen and used in Thailand. Its obverse is King Bhumibol Adulyadej in the uniform of the Supreme Head of the armed forces.
This series was published to commemorate the contribution of Chakri Dynasty’s Monarchs in the development of agriculture, science religion and finance. Hence, you will see that its reverse side contains images of a telescope, celestial globe, temple, etc.
Series 16 Thai Baht Banknotes
Series 16 was issued between 2012 and 2015. Its obverse is King Bhumibol Adulyadej in the Royal House of Chakri gown.
Series 17 Thai Baht Banknotes
King Vajiralongkorn is the King of Thailand since 2016 and Series 17 with the obverse of King Vajiralongkorn in the uniform of the commander of the Royal Thai Air Force was issued in 2018.
Series 17 features the Kings of Chakri Dynasty on its reverse side.