In islam, is it permissible to work in an accounting firm where some clients are engaged in haraam business activities?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

It is forbidden in Islam to audit accounts for entities that have prohibited activities such as Riba-based banks, alcohol factories, etc.

The Fatwa of the Standing Committee reads:

"Auditing accounts of Riba-based banks and verifying or examining them is not permissible, because it is cooperating in sin and transgression, while Allah Says (what means): {And cooperate in righteousness and piety, but do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty.} [Quran 5:2]"

As for the ruling on working in a general accounting firm, which has some clients who are involved in prohibited activities; then it is permissible to work in institutions who might be involved in some forbidden activities if the principle is that the majority of their activities are permissible, if the employee will not engage in doing what is forbidden.

Therefore, if the majority of the work of the accounting firm is permissible and the field of work of the employee is not related to audit the entities with prohibited activities, then there is no harm on him in doing this work, otherwise it is forbidden.

Allah knows best.