However, the colours blue, black and green are avoided as they are typically associated with death and mourning. It is thought to be disrespectful to open a gift in the presence of the giver unless invited to do so.

In Thailand, the primary color to avoid in most social and celebratory contexts is black, as it is strictly associated with mourning and funerals. Wearing an all-black outfit to a wedding, a birthday party, or a hospital visit is considered a significant faux pas and is thought to bring bad luck to the hosts or the patient. While black is perfectly acceptable for business attire or casual evening wear in modern Bangkok, it should never be worn to "festive" events. Historically, red was also avoided at weddings because it was associated with blood and seen as an ill omen for the couple, though this has softened in 2026 due to Chinese-Thai influence where red is seen as lucky. Additionally, when visiting royal palaces or high-ranking temples, it is respectful to avoid overly bright, neon, or "flashy" colors in favor of muted, respectful tones. You should also be aware of the "Color of the Day" tradition (e.g., Yellow for Monday, Pink for Tuesday); while tourists aren't expected to follow this, wearing the "wrong" color for a specific day isn't offensive, but avoiding black during a celebration is a vital sign of cultural sensitivity.