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, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
First of all, we should say to you, dear brother, that it is desirable to bid farewell to your family, your relatives, your friends and your neighbors when you go for Hajj and you should seek their forgiveness.
The Fiqh Encyclopedia reads: “It is desirable for anyone who is going for Hajj or ‘Umrah to bid farewell to his/her family, relatives and friends because he/she is a traveler like all other travelers.”
Moreover, Ad-Durr Al-Mukhtaar, a Hanafi book, reads: “Among the Sunan [plural of Sunnah, i.e. a recommended act] of Hajj and its etiquettes is that the traveler who is going for Hajj bids farewell to the mosque – the mosque of his area – by performing two Rak’ahs and bids farewell to his acquaintances, and seeks their forgiveness and supplication.”
However, if you want to hide your going for Hajj, then you are not obliged in principle to tell anyone that you are going for Hajj but we advise you to inform your close relatives, like your parents, wife and children and brothers and sisters, about your travel even if you do not want to tell them that you are going for Hajj; because if you travel without informing them, they may probably be panicked and frightened and they may think that something bad has happened to you. Indeed, the Prophet told one of his Companions when he hid the luggage of his Muslim brother and the latter got frightened: “It is not permissible for a Muslim to frighten another Muslim.” [Ahmad, Abu Dawood]
Al-Munaawi said in his book entitled Faydh Al-Qadeer about the reason for the prohibition: “This is because it is causing harm and distress to him...” There is no doubt that your sudden absence from them causes harm and fright to them.
Allaah Knows best.