Instructions for voting by telephone and over the Internet are printed on the proxy cards. Proxy Solicitation We are making this proxy solicitation and will bear the expense of preparing, printing and mailing this notice and proxy statement.

Patterson Chairman, President and CEO *Avient Sustainable Solutions definitions aligned with FTC 2012 Guide for the Use of Environmental Marketing Claims (“Green Guides”) **2020 is Pro forma to include full year of the Clariant Color business 2016 2017 2018 2019 2020PF** 2021 Revenue from Sustainable Solutions* 2016–2021 Lightweighting Eco-conscious Sustainable Infrastructure Human Health & Safety Reduced Energy Use Bio-polymers Recycle Solutions VOC Reduction 12% Organic CAGR End Market Transformation* � �� �� �� �� �� �� Transportation Building & Construction Healthcare Packaging Consumer 57% 21% 57% 22% 14% 43% 11% 10% 8% 10% 4% 19% 23% 15% $790M $550M $405M $455M $340M $915M 2006 2021 2006 2021 *End market revenue as a percent of total United States Securities and Exchange Commission Washington, DC 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to . Magna Colours), a market leader in sustainable, water-based inks technology for the textile screen printing industry, for the purchase price of $47.6 million, net of cash acquired. Magna Colours), a market leader in sustainable, water-based inks technology for the textile screen printing industry, for the purchase price of $47.6 million, net of cash acquired.

Our sustainable solutions portfolio helps our customers to solve complex sustainability challenges, including enabling the use of more recycled content, or biopolymers, sustainable infrastructure, human health & safety, lightweighting, reducing volatile organic compounds, reducing energy usage, and offering eco-conscious solutions. In support of this climate transition, Avient has focused its continuous improvement efforts on: • Investing in resources and existing technologies to optimize operations, including improvements in energy efficiency and waste reduction • Maximizing the use of renewable energy in our operations • Adopting new technologies in our global network of facilities • Continuing to develop new and innovative products that have sustainability attributes that decrease GHG emissions and enable the world’s transition to a lower-carbon economy • Advancing circularity in our operations and our customers’ products • Partnering with our suppliers to enhance the eco-efficiency of our supply chain (continues on next page) Climate Change Energy and Greenhouse Gas (GHG) Emissions Avient Joins Better Plants Program Avient proudly announced its partnership with the U.S.

Our sustainable solutions portfolio helps our customers to solve complex sustainability challenges, including enabling the use of more recycled content, or biopolymers, sustainable infrastructure, human health & safety, lightweighting, reducing volatile organic compounds, reducing energy usage, and offering eco-conscious solutions. In support of this climate transition, Avient has focused its continuous improvement efforts on: • Investing in resources and existing technologies to optimize operations, including improvements in energy efficiency and waste reduction • Maximizing the use of renewable energy in our operations • Adopting new technologies in our global network of facilities • Continuing to develop new and innovative products that have sustainability attributes that decrease GHG emissions and enable the world’s transition to a lower-carbon economy • Advancing circularity in our operations and our customers’ products • Partnering with our suppliers to enhance the eco-efficiency of our supply chain (continues on next page) Climate Change Energy and Greenhouse Gas (GHG) Emissions Avient Joins Better Plants Program Avient proudly announced its partnership with the U.S.

• You can be confi dent that, in formulating and manufacturing our materials, we use sustainable practices to provide long- term product viability and sound environmental stewardship • You can expect that the materials we produce contain only ingredients that conform to accepted legal and regulatory compliance guidelines • You can trust that PolyOne materials meet the rigorous quality and safety management standards required across the globe • You can be certain that PolyOne meets or exceeds the material safety data reporting requirements of your country or region • When you choose PolyOne, you can be confi dent our products will help you meet or exceed today’s stringent compliance standards HELPING CUSTOMERS MEET THEIR GOALS THROUGH MATERIAL SCIENCE 66672.indd main_6 3/25/19 4:00 PM 7 *PolyOne Sustainable Solutions defi nitions aligned with FTC 2012 Guide for the Use of Environmental Marketing Claims (“Green Guides”) 2016 2017 2018 20% INCREASE HELPING CUSTOMERS BECOME MORE SUSTAINABLE $480M $440M $400M $1.3 BILLION IN REVENUE FROM SUSTAINABLE SOLUTIONS* 2016–2018 Lightweighting Reduced Material Requirements Improved Recyclability Renewable Energy Applications Eco-conscious Composition Bio-derived Content Reduced Energy Use Volatile Organic Compound Reduction PolyOne off ers a broad portfolio of technologies that help our customers—and our planet—be more sustainable. Vice President of Operations, Michelman (a manufacturer of advanced materials used in coatings, printing & packaging and industrial markets) from May 2005 to June 2007. Color and additive solutions include an innovative array of colors, special effects and performance-enhancing and eco-friendly solutions.

a technology company with a product and services portfolio of personal systems, printers, and 3D printing solutions, since 2022. Wulfsohn EXECUTIVE COMPENSATION 76 PROXY STATEMENT 2023 | Annual Meeting of Shareholders MISCELLANEOUS PROVISIONS INTERNET AVAILABILITY OF PROXY MATERIALS In accordance with rules and regulations adopted by the Securities and Exchange Commission, we may furnish proxy materials by providing internet access to those documents, instead of mailing a printed copy of our proxy materials to each shareholder. MISCELLANEOUS 78 PROXY STATEMENT 2023 | Annual Meeting of Shareholders PROXY SOLICITATION Avient is making this proxy solicitation and will bear the expense of preparing, printing and mailing this notice and proxy statement.

Our sustainable solutions portfolio helps our customers to solve complex sustainability challenges, including enabling the use of more recycled content, or biopolymers, sustainable infrastructure, human health & safety, lightweighting, reducing volatile organic compounds, reducing energy usage, and offering eco-conscious solutions. In support of this climate transition, Avient has focused its continuous improvement efforts on: • Investing in resources and existing technologies to optimize operations, including improvements in energy efficiency and waste reduction • Maximizing the use of renewable energy in our operations • Adopting new technologies in our global network of facilities • Continuing to develop new and innovative products that have sustainability attributes that decrease GHG emissions and enable the world’s transition to a lower-carbon economy • Advancing circularity in our operations and our customers’ products • Partnering with our suppliers to enhance the eco-efficiency of our supply chain (continues on next page) Climate Change Energy and Greenhouse Gas (GHG) Emissions Avient Joins Better Plants Program Avient proudly announced its partnership with the U.S.

Color and additive solutions include an innovative array of colors, special effects and performance-enhancing and eco-friendly solutions. Color and additive solutions include an innovative array of colors, special effects and performance-enhancing and eco-friendly solutions.

Instructions for voting by telephone and over the Internet are printed on the proxy cards. 5 ELECTION OF BOARD OF DIRECTORS PROPOSAL 1— ELECTION OF BOARD OF DIRECTORS Our Board currently consists of 11 Directors. Proxy Solicitation We are making this proxy solicitation and will bear the expense of preparing, printing and mailing this notice and proxy statement.

Color and additive solutions include an innovative array of colors, special effects and performance-enhancing and eco-friendly solutions. Color and additive solutions include an innovative array of colors, POLYONE CORPORATION 73 special effects and performance-enhancing and eco-friendly solutions.