X0306 4 2021-04-06 0 0001782754 AZEK Co Inc. AZEK 0001192519 NICOLETTI RALPH J 1330 W. FULTON STREET SUITE 350 CHICAGO IL 60607 0 1 0 0 CFO Class A Common Stock 2021-04-06 4 S 0 15000 44.39 D 406976 D The sale of shares reported on this Form 4 was effected pursuant to a Rule 10-b(5)-1 trading plan adopted by the Reporting Person on January 22, 2021. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.01 to $44.75, inclusive. The reporting person undertakes to provide to AZEK, any security holder of AZEK, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. Includes 139,304 restricted shares of the Issuer's Class A common stock that vest in equal installments on January 9, 2022, 2023 and 2024 and 3,101 restricted stock units that vest in equal installments on December 4, 2021, 2022 and 2023. /s/ Paul J. Kardish, attorney-in-fact for Ralph J. Nicoletti 2021-04-07