Md. Code, Local Government § 9–113

(a) In this section, “chief executive officer” means:

(1) the mayor of Baltimore City; or

(2) the County Executive of Montgomery County.

(b) This section applies only to Baltimore City and Montgomery County.

(c) Except as provided in subsection (d) of this section, a candidate for chief

executive officer shall be a resident of the county for at least 6 months before the

general election for chief executive officer.

(d) If the charter of a county contains a durational residency requirement

that is longer than 6 months, the longer durational residency requirement shall be

retained if the governing body of the county reaffirms the requirement by enactment

of an ordinance no later than 4 weeks before the filing deadline specified in § 5–303(a)

of the Election Law Article.