All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If you had not performed your obligatory ‘Umrah before, it is permissible for you to go for ‘Umrah without your husband’s permission as long as you travel with your Mahram (i.e. a person whom one is permanently prohibited from marrying due to suckling, marital, or blood relations) because according to the view of many jurists ‘Umrah is mandatory.
The jurists stated that a husband has no right to prevent his wife from the obligatory ‘Umrah. However, it is desirable for you to seek his permission, so try your best to do so.
On the other hand, if your ‘Umrah is optional, it is not permissible for you to travel without his permission. For more benefit, please refer to Fatwa 81584.
Allaah Knows best.