Va. Code Ann. § 24.2-403

Any person who is otherwise qualified and will be 18 years of age on or before the day of the next general election shall be permitted to register in advance and also vote in any intervening primary or special election. Notwithstanding any other provision of law to the contrary, any person who is otherwise qualified and will be 18 years of age on or before the day of the next November general presidential election shall be permitted to register in advance of and also vote in any intervening presidential primary and any other primary held on the same day as the presidential primary.