Fiqh-us-Sunnah Volume 5, Hajj and ‘Umrah, Fiqh 5.012.

It is desirable for a woman to seek her husband’s permission for the prescribed Hajj. Then if he grants her the permission she may leave for Hajj; in case he refuses to give permission, she may still proceed for Hajj, for a husband should not forbid his wife from performing obligatory Hajj. It is an obligatory act of worship. It is unlawful to obey anyone in something that involves disobedience to Allah. A woman should perform obligatory Hajj as soon as possible, just as she should offer her prescribed daily prayers at their earliest prescribed times. In either case a husband has no right to prevent his wife from doing what is her obligatory duty. The same applies when a wife has vowed a Hajj, because it is obligatory like the prescribed Hajj. In the case of supererogatory Hajj, however, the husband may prevent his wife, and the wife must obey her husband. This is supported by a hadith reported by AdDaraqutni on the authority of Ibn ‘Umar who narrated that while speaking about a wealthy lady whose husband had refused to give her permission to perform Hajj, the Prophet (peace be upon him) said: “She must not go for Hajj except by her husband’s permission.”