No, it is not necessary. Visitors are not expected to bring gifts or offerings when visiting temples or monasteries.
However, small offerings are welcome and appreciated. Traditionally, Bhutanese pilgrims may offer a kadar (ceremonial scarf), a small amount of loose change, or make offerings such as butter lamps or fruits. If you wish to participate, these items are usually available for purchase near major temples and monasteries.
Making an offering is entirely optional and should be done only if it feels meaningful to you.

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