Mourning attire from October 1 to 27, 2017, during the royal cremation ceremony of His Majesty King Bhumibol Adulyadej (King Rama IX) is as follows:


- Wear mourning attire, dress in respectful black clothing. Men should wear a white shirt with a black tie.
- Uniforms of each agency are automatically considered mourning attire, with a black ribbon attached to the left sleeve (consider the appropriateness of the uniform color).
- If black clothing is unavailable, wear a respectful colored shirt and attach a black ribbon to the left sleeve.
- Government officials and staff: Operational uniforms or formal attire.
- Male officials and staff: Dress in a white or black shirt with a black tie. If wearing a suit, it should be black or made of black velvet or sheer fabric, with sleeves rolled up appropriately.
- Female officials and staff: Dress in formal attire suitable for the ceremony, using all black accessories.
- General public: All black is best; wear black clothing as a base, with white or gray accents allowed.
- If no black outfit is available for mourning: wear a black shirt or attach a black ribbon.
- Clothing with logos should not be worn as it is not approved by royal decree and is inappropriate.



Mourning attire from October 1 to 27, 2017, is divided into four periods as follows:
- Period of remembrance for royal benevolence: October 1-12, 2017
- Anniversary of passing: October 13-24, 2017
- Royal cremation ceremony: October 25-26, 2017
- Period of lifting the mourning: October 28-29, 2017