Md. Code Ann., Tax-Prop. § 10-105 — § 10-105

(a) The Mayor and City Council of Baltimore City or the governing body of a county or of a municipal corporation may impose, by law, a county or municipal corporation property tax on real property that, during the period from January 1 to March 30, both inclusive, is completed or otherwise is initially added to the tax roll. If imposed, the tax shall be for the 3-month period from April 1 to June 30, both inclusive, at 25% of the annual county or municipal corporation tax rate that is in effect for that taxable year.
(b) The county or municipal corporation property tax imposed under this section is due on the later of:
(1) April 1 of the taxable year; or
(2) the date that the tax bill is received or reasonably should have been received or is available.
(c) County or municipal corporation property tax imposed under this section may be paid without interest or penalty on or before 30 days after the date the tax bill is mailed or made available.