Sadaqah is a form of voluntary charity in Islam. Unlike Zakat (which is obligatory), Sadaqah can be given at any time, in any amount, and to anyone in need — purely for the sake of pleasing God.
It does not have to be monetary. A kind word, helping someone carry groceries, or even smiling at a stranger is considered Sadaqah in Islamic tradition. The Prophet Muhammad said: "Every act of goodness is Sadaqah."
In Islamic banking and finance, Sadaqah is encouraged as a way to redistribute wealth and support community welfare. Some Islamic financial institutions channel a portion of their profits toward Sadaqah-based programs.