I know it's late reply but still..
Look, there are some legalities of age too plus there are no sides of this question, one, when you have to come to KSA from another country and other side, when you live here and want to perform Hajj.
According to Islam, its obligatory to perform hajj on : "An adult" Muslim of a sane mind, an able body and having means to bear the expenses must perform this act of worship once in his/her lifetime. There should be peace on the way to Makkah and there should be no hindrance or restriction in traveling to Mecca. Hajj is not obligatory for children, the sick, and those who are unable to bear the expenses for Hajj.
Coming on the age legalities, in 2009 KSA put ban on under 12 and over 65 to perform Hajj, the Saudis took the measure to check the spread of the Swine Flu disease, a few cases of which had been isolated in the Kingdom.
But it has lifted the next year. So it is possible that children wud not be allowed in emergency cases.
Money also matters when you're coming from an other country coz it takes lacks to perform hajj, this is why people dont like to take kids with them.
Pls note
- Children between the ages of seven (7) and fifteen (15) should only pay half of the above-mentioned amount.
- Children under the age of seven (7) do not need tp pay.
- No applicant under the legal age of eighteen (18) will be granted a Hajj visa if not accompanied by his family.
(this is for males. women always need a "mahram" with her to perform hajj/umrah)
Source:
http://www.saudiembassy.net/services/hajj_requirements.aspx
As far as People who are living here are concern, they can only perform hajj once in five years.
P.S I performed hajj when I was 6 but it was not my farz hajj, since then things didn't worked my way. Hopefully I'll get a chance soon. inshAllah.
from islamic point of view even a before 18 guy can go even without his family, considering that 'he' is adult (which i guess 15 above is safe to assume)... i dunno about adolescents. and i said 'he' because i dunno the ruling about an adult 'she'...
all this was written just to emphasise that 18 has got nothing to do with it, unless you are talking about restrictions to travel on underage people and the requirement for them to be accompanied etc... which i guess nabeha has answered