Does the wife has the right to know about the family budget?

Firstly:

Islam has made it obligatory upon the husband to spend on his wife on a reasonable basis, according to what he can afford. And it does not oblige the wife to spend on herself even if she is rich, except with her willing consent, and that is by way of kindness and helping her husband.

Among the things that the Prophet (blessings and peace of Allah be upon him) said in his sermon during the Farewell Pilgrimage is the following: “Fear Allaah with regard to women …  Their rights over you are that you should provide for them and clothe them in a reasonable manner.”

Narrated by Muslim, 1218.

An-Nawawi said in Sharh Muslim, 8/184: This indicates that it is obligatory to spend on the wife’s maintenance and clothing. This is established by scholarly consensus. End quote.

For more details please see the answer to question no. 3054

Secondly:

It is not permissible for the husband to take anything from his wife’s salary except what she gives willingly. Anything he takes apart from that is haram.

For information on advice to both spouses concerning such matters, please see the answer to question no. 126316

Thirdly:

If the husband spends on his wife from his own wealth on a reasonable basis, then it is not within her rights that he should tell her how much he has and how much his savingsare, or how he plans his finances and so on.

Fourthly:

If the wife contributes her salary to the family expenses, then it is her right to know where and how her money was spent, and how much of the monthly household budget she is supporting and so on, and this becomes more important if she asks for that. Otherwise it is within her rights to withhold her contribution altogether.

And Allah knows best.