May a wife in her ʿiddah leave the house or go to work?

A wife in her ʿiddah must stay in the marital home, but may go out for needs such as work, treatment or important business.
Allah forbids husbands to turn their wives out of the house during the ʿiddah, and the wife too should not leave without reason. In the Shafi'i school, a wife in the ʿiddah of a revocable talaq (raj'i) needs her husband's permission to go out because she is still under his maintenance; a wife in the ʿiddah of an irrevocable talaq (ba'in) or of death may go out during the day for needs and return to spend the night at home.
Working to earn a living counts as a need. Avoid long journeys or spending the night elsewhere without an emergency. See ʿiddah & rujuk.