Va. Code § 15.2-2248
The subdivision regulations adopted by a municipality within the counties of Giles, Clarke, Culpeper, Loudoun or Mecklenburg shall apply within the corporate limits and may apply beyond, if the municipal ordinance so provides, within the distance therefrom set out below:
Where the corporate limits of two municipalities are closer together than the sum of the distances from their respective corporate limits as above set forth, the dividing line of jurisdiction shall be halfway between the limits of the overlapping boundaries.
The foregoing distances may be modified by mutual agreement between the governing bodies concerned, depending upon their respective areas of interest, provided such modified limits bear a reasonable relationship to natural geographic considerations or to the comprehensive plans for the area. Any such modification shall be set forth in the respective subdivision ordinances, by map or description or both.
No such regulations or amendments thereto shall be finally adopted by any such municipality until the governing body of the county in which such area is located shall have been duly notified in writing by the governing body of the municipality or its designated agent of such proposed regulations, and requested to review and approve or disapprove the same; and if such county fail to notify the governing body of such municipality of its disapproval of such plan within forty-five days after the giving of such notice, such plan shall be considered approved. Provided, however, that in any county which has a duly appointed planning commission, the governing body or the council shall send a copy of such proposed regulations or amendments thereof to such commission which shall review and recommend approval or disapproval of the same. The county commission shall not take any such action until notice has been given and a hearing held as prescribed by § 15.2-2204. Such hearing shall be held by the county commission within sixty days after the giving of notice by the municipality or its agent. Such commission shall forthwith after such hearing make its recommendations to the governing body of the county which shall within thirty days after such hearing notify the municipality of its approval or disapproval of such regulations and no regulations effective beyond the corporate limits shall be finally adopted by the municipality until notification by the governing body of the county, except that if the county fails to notify the governing body of the municipality of its disapproval of such regulations within ninety days after copy of the regulations or amendments thereof are received by the county commission, the regulations shall be deemed to have been approved.
Va. Code § 15.2-2248