Praise be to Allaah.
It is not permissible to delay paying zakaah from the time
when it becomes due for the one for whom it is obligatory, as we have
explained in the answer to question no.
67578. What you have mentioned is
not an excuse for delaying it when there are so many people who are entitled
to it in Muslim countries.
If you think that these families are more deserving than
others of receiving your zakaah, then there is nothing wrong with you giving
the rent before it becomes due, if you think it most likely that they will
be staying in the same house or, if they move, they will not lose the money.
Giving it ahead of time may be a cause of reducing some of the rent for
them.
It is also possible to pay some of the zakaah for the coming
year in advance in the month of Muharram, and to pay the rent that is due on
time, from the zakaah on your wealth. Then you can subtract what you already
paid from next year’s zakaah. See the answer to question no.
98528
You can also pay the rent on these families’ homes directly
to the landlord, because when the rent becomes due, the renter is then in
debt; in that case it is permissible to give the money directly to the one
to whom the debt is owed. See the answer to question no.
46209.
And Allah knows best.