UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

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ADVANCED DRAINAGE SYSTEMS, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Stockholder Meeting to Be Held on July 23, 2020.

Advance Drainage Systems, Inc./WMS     ADS ADVANCED DRAINAGE SYSTEMS, INC./WMS 4640 TRUEMAN BLVD. HILLIARD, OH 43026   D18745-P40408 Meeting Information Meeting Type: Annual Meeting For holders as of: May 29, 2020 Date: July 23, 2020 Time: 10:00 AM Eastern Time Location: Meeting live via the Internet-please visit www.virtualshareholdermeeting.com/WMS2020. The company will be hosting the meeting live via the Internet this year. To attend the meeting via the Internet please visit www.virtualshareholdermeeting.com/WMS2020 and be sure to have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the following page). You are receiving this communication because you hold shares in the company named above or you are a participant in the Advanced Drainage Systems, Inc. Employee Stock Ownership Plan. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. See reverse side of this notice to obtain proxy materials and voting instructions

Before You Vote

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NOTICE AND PROXY STATEMENT 10-K WRAP

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D18746-P40408

Voting Items

The Board of Directors recommends you vote

FOR all of the nominees listed and FOR proposals

2, 3, 4 and 5.

1. Election of Directors 1a. D. Scott Barbour 1b. Michael B. Coleman 1c. Tanya Fratto 1d. Carl A. Nelson, Jr. 1e. Anesa T. Chaibi   2. Approval, in a non-binding advisory vote, of the compensation for named executive officers.   3. Ratification of the appointment of Deloitte & Touche LLP as the Company's Independent Registered Public Accounting Firm for fiscal year 2021.   D18747-P40408 4. Approval of amendments to the Company's Amended and Restated Certificate of Incorporation (the "Certificate of Incorporation") to declassify the Board of Directors over a three-year period and provide that directors elected on or after the 2021 Annual Meeting serve for one-year terms.   5. Approval of amendments to the Company’s Certificate of Incorporation to eliminate provisions requiring supermajority stockholder approval to amend certain provisions of the Certificate of Incorporation and to amend the Bylaws.   NOTE: Such other business as may properly come before the meeting or any adjournment thereof.

D18748-P40408