There is nothing wrong with giving zakaah to workers or servants if they are entitled to zakaah, such as if they are poor or needy and the salary that they receive is not sufficient for their and their family’s needs. Allaah has mentioned those who are entitled to zakaah in the verse where He says (interpretation of the meaning):
“As-Sadaqaat (here it means Zakaah) are only for the Fuqaraa’ (poor), and Al‑Masaakeen(the poor) and those employed to collect (the funds); and to attract the hearts of those who have been inclined (towards Islam); and to free the captives; and for those in debt; and for Allaah’s Cause (i.e. for Mujaahidoon — those fighting in a holy battle), and for the wayfarer (a traveller who is cut off from everything); a duty imposed by Allaah. And Allaah is All-Knower, All-Wise”
If they fall into one of these categories, then there is nothing wrong with giving them zakaah.
But it must be noted that it is not permissible to do that in the interests of the boss, such as if he makes them do more work than he agreed with them, or denies them some of their rights, then he gives them zakaah so that they will forfeit their rights and so on.
Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) was asked: If a merchant has workers in his store, or in an institution, and they get a salary of six hundred riyals each, is it permissible for the merchant to give them the zakaah of his wealth?
Yes, it is permissible for him to give them zakaah if they are among those who are entitled to it, such as if they have dependents and their salaries are not enough, or they are in debt and their salary does not pay off the debts, and so on. What matters is that if they are people who are entitled to zakaah, there is nothing wrong with giving it to them even if they are workers or servants working for him. End quote.
Fataawa al-Zakaah, p. 350
Shaykh Dr. ‘Abd al-Kareem ibn ‘Abd-Allaah al-Khudayr was asked: I have some Muslim servants; is it permissible to give the zakaah of my wealth to them?
If the worker uses all his salary and is still in need, in the sense that his salary is not sufficient for him, then there is no shar’i reason why he should not be given zakaah, so that he will have what he needs, subject to the condition that giving zakaah to him does not serve the interests of his boss. End quote.