Under the Hindu Marriage Act, 1955 alone (leaving aside the Prohibition of Child Marriage Act, 2006),…

The age condition in section 5(iii) of the Hindu Marriage Act, 1955 is only directory, enforced through the penal provision in section 18; since it is not a ground of nullity under sections 11 or 12, a minor's marriage remains valid under that Act, not void or voidable. Separately, section 3 of the Prohibition of Child Marriage Act, 2006 makes a child marriage voidable at the option of the party who was a child.