72 Pa. Stat. § 5568k
All penalties and interest imposed on delinquent taxes in cities of the first class and school districts of the first class, for the tax year one thousand nine hundred and thirty-four and all previous years, assessed and levied against any parcel or parcels of real estate, are hereby abated, without the necessity of further action by the authority levying the tax, if said delinquent taxes are paid as hereinafter provided.
In order to receive the benefits of this act, the taxes for the year one thousand nine hundred and thirty-five and all penalties and accrued interest thereon, and thirty-three and one-third per centum of the delinquent taxes due for the tax year one thousand nine hundred and thirty-four and for all previous years shall be paid on, or before, the first day of November, one thousand nine hundred and thirty-six; thirty-three and one-third per centum on, or before, the first day of November, one thousand nine hundred and thirty-seven; thirty-three and one-third per centum on, or before, the first day of November, one thousand nine hundred and thirty-eight: And provided, That the respective current taxes on such parcel or parcels of real estate for the years subsequent to the year one thousand nine hundred and thirty-six during such installment periods, assessed and levied by such taxing authority, shall be paid during the then current year before they become delinquent. If and whenever any of the said current taxes, or any of the said installments, are not paid when due and payable as herein provided, then, and in that event, there shall become due and payable for such year, a sum equal to one-third of what would have been the total amount of the abated penalties and interest had the payment in question been made on time, this sum to be in addition to the other payments required to be paid under this act during that year, which said additional sum shall be payable, and must be paid at the time the next succeeding installment payment becomes due under this act. If such additional sum is not so paid, then the total amount of the abated penalties and interest, less the aggregate of any such additional sums theretofore paid, shall be revived and added to the unpaid taxes with the same force and effect as if such abated penalties and interest, or portion thereof, had never been abated, and the taxpayer shall not thereafter be entitled to any further benefits or privileges under this act.
72 P.S. § 5568k