When should I remove the red kalāvā (mauli) thread tied on my wrist?

there is no strict rule; many remove it after some days or at the next pūjā, and dispose of it respectfully.

The kalāvā or mauli is the red-and-yellow cotton thread tied on the wrist during a saṅkalpa or pūjā as a protective blessing and a sign that you took part in the rite. Customarily it is tied on the right wrist for men and unmarried girls, and on the left for married women, though this varies.

There is no scriptural deadline for removing it. Common family practices include keeping it until it fades or loosens, removing it after a week or so, or replacing it at the next pūjā or festival — some choose a Tuesday or Saturday. If it becomes dirty, wet for long periods, or irritates the skin, simply take it off.

Do not throw it in the dustbin. Place it under a tree such as peepal or tulasī, in the garden soil, or in flowing water. Removing it does not remove the blessing; the prayer has already been offered.

Dispose under a tree or in garden soil · Source: common family practice

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