53 Pa. Stat. § 15951
Whenever local assessments or liens are imposed upon certain property holders in any city of the first class in this Commonwealth, the authorities of such city may, by general ordinance or by ordinance relating to the specific improvement, prescribe that such assessments may be paid in not more than ten equal installments, payable at such times as may be fixed by ordinance, the last thereof not to be more than ten years after the completion of the work of the improvement for which it is assessed. The installments shall bear interest at the rate of not more than six per centum per annum, commencing at such time as may be fixed by ordinance. If any of said installments shall remain unpaid for two months after the same shall become due and payable, the whole of the assessment remaining unpaid shall be due and payable.
Any person, upon whom such assessment has been made, may pay all or as much as he chooses of such installment before the same is due.
53 P.S. § 15951