Originally, the Muslim who intends to perform `Umrah or Hajj must not pass the miqat without entering ihram, i.e., declaring the intention to perform Hajj, `Umrah, or both of them. The intention is not completed without Talbiyah. if one uttered Talbiyah with the other Muslims at the miqat, then their ihram would be valid. Also, if one uttered it alone while wearing the clothes of ihram before reaching the miqat, our ihram would be valid. Whereas if one forgot to utter Talbiyah until they passed the miqat while they were still in `Umrah, they have to return to the miqat and enter ihram. If they returned to their country after performing `Umrah, they have to slaughter an animal by sending its price to someone who can do so at Al-Haram, or slaughter it by themself if they will go there later. If one cannot afford to slaughter, they have to fast 10 days.
Sheikh `Atiyyah Saqr, former head of Al-Azhar Fatwa Committee, states the following: It is not permissible to the one who intends to perform Hajj, `Umrah, or both to pass the defined miqat without entering ihram, as Ibn `Abbas reported on the authority of the Prophet (peace and blessings be upon him) that he said, “And these miqats are for the people at those very places, as well as for those who come through those places with the intention of performing Hajj and `Umrah” (Al-Bukhari and Muslim).
Thus, if he passes the miqat without entering ihram, he is obliged to return to the miqat and enter ihram. If he does not return and enters ihram from his place, he is obliged to slaughter a sheep.
According to the fatwas of Al-Azhar, the one who does not enter ihram without having any excuse is obliged to slaughter an animal. If he has an excuse, he is obliged to offer fidyah (expiation): to fast ten days, to feed six poor persons each with half a saa` (a cubic measurement of grain that weighs around 3.2kg) of staple food, or to slaughter an animal like that of Hajj at-tamattu`.
Moreover, Sheikh `Abd al-`Aziz ibn Baz (may Allah have mercy upon him) said about the woman who entered ihram in a place other than the miqat: She is obliged to slaughter a sheep; if she cannot afford to slaughter, she has to fast 10 days. The sheep must be slaughtered in Makkah and distributed among the poor in Al-Haram (Sanctuary), and she must not eat any of it. As for fasting, it is allowed at any place.
Allah Almighty knows best.