QS. Al-Baqarah [2:196]

wa‑atimmuu alhajja waal'umrata lillaahi fa‑in uhsirtum famaa istaysara mina alhadyi walaa tahliquu ruuusakum hattaa yablugha alhadyu mahillahu faman kaana minkum mariidhan aw bihi adzan min ra'sihi fafidyatun min shiyaamin aw shadaqatin aw nusukin fa‑idzaa amintum faman tamatta'a bil'umrati ilaa alhajji famaa istaysara mina alhadyi faman lam yajid fashiyaamu tsalaatsati ayyaamin fii alhajji wasab'atin idzaa raja'tum tilka 'asyaratun kaamilatun dzaalika liman lam yakun ahluhu hadirii almasjidi alharaami wattaquu allaaha wa'lamuu anna allaaha syadiidu al'iqaabi

And complete the Hajj and 'umrah for Allah. But if you are prevented, then [offer] what can be obtained with ease of sacrificial animals. And do not shave your heads until the sacrificial animal has reached its place of slaughter. And whoever among you is ill or has an ailment of the head [making shaving necessary must offer] a ransom of fasting [three days] or charity or sacrifice. And when you are secure, then whoever performs 'umrah [during the Hajj months] followed by Hajj [offers] what can be obtained with ease of sacrificial animals. And whoever cannot find [or afford such an animal] - then a fast of three days during Hajj and of seven when you have returned [home]. Those are ten complete [days]. This is for those whose family is not in the area of al-Masjid al-Haram. And fear Allah and know that Allah is severe in penalty. [196]

— Sahih International