Conditions for the person
Islam, sanity, and, for the rite to be obligatory where a school holds it obligatory, maturity and financial and physical capacity. A child's Umrah is valid and rewarded but does not discharge any obligation.
There is no Saudi visa restriction by age. Women aged 18 and over may apply and travel without a mahram under current visa rules, though schools differ on the fiqh.
The pillars and the wajib acts
Pillars (arkan): ihram with intention, tawaf of seven circuits, sa'i of seven lengths, and halq or taqsir. Omitting any of these means the Umrah is not complete.
Wajib: entering ihram from the miqat, and covering the awrah during tawaf. Omitting a wajib requires a penalty, typically a sacrifice, but the Umrah stands.
The Hanafi school classifies sa'i as wajib rather than a pillar, which is the main point of difference.
Common errors that affect validity
Fewer than seven circuits of tawaf, or seven round trips of sa'i instead of seven lengths. Performing sa'i before tawaf. Performing tawaf without wudu, which the majority hold invalidates it. Cutting hair before completing sa'i.
None of these are common among people who have read the sequence once. The genuinely common error remains scented products after entering ihram, which is a penalty rather than an invalidation.
Where scholars differ
Whether Umrah is obligatory (Shafi'i and Hanbali) or a confirmed sunnah (Hanafi and Maliki). Whether sa'i is a pillar or wajib. Whether wudu is a condition for tawaf. These are long-settled differences within orthodox scholarship, not disputes, follow the position of your own school.
Common questions
What are the pillars of Umrah?
In the majority view there are four: entering ihram with the intention, performing tawaf of seven circuits, performing sa'i of seven lengths between Safa and Marwah, and completing with halq or taqsir. Omitting a pillar means the Umrah is not complete. The Hanafi school classifies sa'i as wajib rather than a pillar.
What invalidates Umrah?
Omitting a pillar, fewer than seven circuits of tawaf, sa'i before tawaf, or cutting hair before completing sa'i. The majority also hold that performing tawaf without wudu invalidates it. Breaches such as applying perfume after entering ihram carry a penalty but do not invalidate the rite.
Is Umrah obligatory?
The schools differ. The Shafi'i and Hanbali schools hold Umrah obligatory once in a lifetime for those able to perform it. The Hanafi and Maliki schools hold it to be a confirmed sunnah rather than an obligation. All four agree it carries great reward and may be repeated freely.
Can children perform Umrah?
Yes. A child's Umrah is valid and rewarded, though it does not discharge any obligation that would fall on them after maturity. Boys who have not reached puberty wear ihram, with the restrictions applying less strictly than to adults.