Maryland Code, Tax-Property § 10-103

(a) Except as provided by § 10-104 of this subtitle, real property that during the period from July 1 to December 31, both inclusive, is completed or is otherwise initially added to the tax roll shall be taxed for the 6-month period from January 1 to the following June 30, both inclusive, at 50% of the annual State, county, municipal corporation, or taxing district property tax rate that is in effect for that taxable year.

(b) The property tax imposed under this section is due on the later of:

(c) 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.