Tax Fees. Tax services include tax compliance, tax advice and tax planning. Tax Considerations.

To access Avient’s news library online, please visit www.avient.com/news. https://www.avient.com/news 4 Pro Forma for Acquisition of Avient Protective Materials business (APM) On September 1, 2022, the company acquired DSM’s Protective Materials business, the foundation of which is the renowned technology and globally admired brand of Dyneema®, the World’s Strongest Fiber™. Three Months Ended December 31, 2022 2021 GAAP Results Special Items Adjusted Results GAAP Results Special Items Adjusted Results (Loss) income from continuing operations before income taxes $ (77.4) $ 104.3 $ 26.9 $ 27.4 $ 20.5 $ 47.9 Income tax benefit (expense) - GAAP 60.8 — 60.8 (17.1) — (17.1) Income tax impact of special items (Attachment 3) — (26.8) (26.8) — (4.1) (4.1) Tax adjustments (Attachment 3) — (39.2) (39.2) — 7.5 7.5 Income tax benefit (expense) $ 60.8 $ (66.0) $ (5.2) $ (17.1) $ 3.4 $ (13.7) Effective Tax Rate(1) 78.5 % 19.6 % 62.4 % 28.6 % (1) Rates may not recalculate from figures presented herein due to rounding 15 Year Ended December 31, 2022 2021 GAAP Results Special Items Adjusted Results GAAP Results Special Items Adjusted Results Income from continuing operations before income taxes $ 63.8 $ 194.0 $ 257.8 $ 203.5 $ 57.1 $ 260.6 Income tax benefit (expense) - GAAP 19.3 — 19.3 (51.9) — (51.9) Income tax impact of special items (Attachment 3) — (49.4) (49.4) — (13.0) (13.0) Tax adjustments (Attachment 3) — (28.4) (28.4) — 5.9 5.9 Income tax expense $ 19.3 $ (77.8) $ (58.5) $ (51.9) $ (7.1) $ (59.0) Effective Tax Rate(1) (30.2)% 22.7 % 25.5 % 22.7 % (1) Rates may not recalculate from figures presented herein due to rounding Three Months Ended Year Ended Reconciliation of Pro Forma Adjusted Earnings per Share December 31, 2022 Net (loss) income from continuing operations attributable to Avient shareholders $ (17.0) $ 82.8 Special items, after tax (Attachment 3) 38.3 116.2 Amortization expense, after-tax (Attachment 1) 14.6 49.0 Adjusted net income from continuing operations excluding special items 35.9 248.0 APM pro forma adjustments to net income from continuing operations* 2.5 13.6 APM amortization expense, after tax* — 19.1 Pro forma adjusted net income from continuing operations attributable to Avient shareholders $ 38.4 $ 280.7 Weighted average diluted shares 91.7 92.2 Pro forma adjusted EPS - excluding special items $ 0.42 $ 3.04 * Pro forma adjustment for January - August 2022 APM results (period before Avient ownership) including the impacts of debt financing and prepayments on net income from continuing operations. Reconciliation of Pro Forma Net Debt December 31, 2022 Short-term and current portion of long term debt $ 2.2 Total long-term debt, net 2,176.7 Unamortized discount and debt issuance cost 37.4 Total debt $ 2,216.3 Cash (641.1) Net taxes due from sale of business 105.0 Adjusted cash $ (536.1) Net debt $ 1,680.2 16 Free Cash Flow Calculation December 31, 2022 Cash provided by operating activities 398.4 Capital expenditures (105.5) Free cash flow $ 292.9 Reconciliation to EBITDA and Adjusted EBITDA Year Ended December 31, 2022 Net (loss) income from continuing operations – GAAP $ 83.1 Income tax (benefit) expense (19.3) Interest expense 119.8 Depreciation and amortization from continuing operations 162.5 EBITDA $ 346.1 Special items, before income tax 194.0 Interest expense included in special items (26.0) Depreciation and amortization included in special items (5.5) APM pro forma adjustments - 8 months 2022* 83.1 Adjusted EBITDA $ 591.7 * Pro forma adjustment for January - August 2022 APM results (period before Avient ownership).

• Factors that could cause actual results to differ materially from those implied by these forward-looking statements include, but are not limited to:  The time required to consummate the divestiture of our resin assets and the satisfaction or waiver of conditions in the sale agreement;  Any material adverse changes in the business supporting the resin assets being sold;  The ability to obtain required regulatory or other third-party approvals and consents and otherwise consummate the proposed divestiture  Our ability to achieve the strategic and other objectives relating to the acquisition of Spartech Corporation, including any expected synergies; our ability to successfully integrate Spartech and achieve the expected results of the acquisition, including, without limitation, the acquisition being accretive;  Disruptions, uncertainty or volatility in the credit markets that could adversely impact the availability of credit already arranged and the availability and cost of credit in the future;  The financial condition of our customers, including the ability of customers (especially those that may be highly leveraged and those with inadequate liquidity) to maintain their credit availability;  The speed and extent of an economic recovery, including the recovery of the housing market;  Our ability to achieve new business gains;  The amount and timing of repurchases, if any, of PolyOne common shares and our ability to pay regular quarterly cash dividends and the amounts and timing of any future dividends;  The effect on foreign operations of currency fluctuations, tariffs, and other political, economic and regulatory risks;  Changes in polymer consumption growth rates in the markets where we conduct business;  Changes in global industry capacity or in the rate at which anticipated changes in industry capacity come online;  Fluctuations in raw material prices, quality and supply and in energy prices and supply;  Production outages or material costs associated with scheduled or unscheduled maintenance programs;  Unanticipated developments that could occur with respect to contingencies such as litigation and environmental matters;  An inability to achieve or delays in achieving or achievement of less than the anticipated financial benefit from initiatives related to working capital reductions, cost reductions, employee productivity goals, and an inability to raise or sustain prices for products or services;  An inability to maintain appropriate relations with unions and employees; and  Other factors affecting our business beyond our control, including, without limitation, changes in the general economy, changes in interest rates and changes in the rate of inflation. • The above list of factors is not exhaustive. • We undertake no obligation to publicly update forward-looking statements, whether as a result of new information, future events or otherwise. The non-GAAP financial measures include: adjusted EPS, earnings before interest, tax, depreciation and amortization (EBITDA), adjusted EBITDA, net debt, Specialty platform operating income, Specialty platform gross margin percentage, adjusted operating income, return on invested capital, net debt/ EBITDA, and the exclusion of corporate charges in certain calculations. Adjusted EPS 2006Y 2007Y 2008Y 2009Y 2010Y*** 2011Y*** 2012Y*** *Net Income attributable to PolyOne common shareholders $ 130.9 $ 40.9 $ (417.0) $ 106.7 $ 152.5 $ 153.4 $ 53.3 SunBelt equity earnings, after tax (68.5) (26.1) (20.8) (19.0) (14.7) (3.7) - Special items, after tax (21.2) 41.4 310.0 (31.0) 15.8 (30.5) 35.7 Tax adjustments (30.0) (30.7) 147.2 (44.9) (88.3) (42.3) 0.5 Adjusted net income $ 11.2 $ 25.5 $ 19.4 $ 11.8 $ 65.3 $ 76.9 $ 89.5 Diluted shares 92.8 93.1 92.7 93.4 96.0 94.3 89.8 Adjusted EPS $ 0.12 $ 0.27 $ 0.21 $ 0.13 $ 0.68 $ 0.82 $ 1.00 *** Restated results to exclude the Resin business.

• Factors that could cause actual results to differ materially from those implied by these forward-looking statements include, but are not limited to:  The time required to consummate the divestiture of our resin assets and the satisfaction or waiver of conditions in the sale agreement;  Any material adverse changes in the business supporting the resin assets being sold;  The ability to obtain required regulatory or other third-party approvals and consents and otherwise consummate the proposed divestiture  Our ability to achieve the strategic and other objectives relating to the acquisition of Spartech Corporation, including any expected synergies; our ability to successfully integrate Spartech and achieve the expected results of the acquisition, including, without limitation, the acquisition being accretive;  Disruptions, uncertainty or volatility in the credit markets that could adversely impact the availability of credit already arranged and the availability and cost of credit in the future;  The financial condition of our customers, including the ability of customers (especially those that may be highly leveraged and those with inadequate liquidity) to maintain their credit availability;  The speed and extent of an economic recovery, including the recovery of the housing market;  Our ability to achieve new business gains;  The amount and timing of repurchases, if any, of PolyOne common shares and our ability to pay regular quarterly cash dividends and the amounts and timing of any future dividends;  The effect on foreign operations of currency fluctuations, tariffs, and other political, economic and regulatory risks;  Changes in polymer consumption growth rates in the markets where we conduct business;  Changes in global industry capacity or in the rate at which anticipated changes in industry capacity come online;  Fluctuations in raw material prices, quality and supply and in energy prices and supply;  Production outages or material costs associated with scheduled or unscheduled maintenance programs;  Unanticipated developments that could occur with respect to contingencies such as litigation and environmental matters;  An inability to achieve or delays in achieving or achievement of less than the anticipated financial benefit from initiatives related to working capital reductions, cost reductions, employee productivity goals, and an inability to raise or sustain prices for products or services;  An inability to maintain appropriate relations with unions and employees; and  Other factors affecting our business beyond our control, including, without limitation, changes in the general economy, changes in interest rates and changes in the rate of inflation. • The above list of factors is not exhaustive. • We undertake no obligation to publicly update forward-looking statements, whether as a result of new information, future events or otherwise. The non-GAAP financial measures include: adjusted EPS, earnings before interest, tax, depreciation and amortization (EBITDA), adjusted EBITDA, net debt, Specialty platform operating income, Specialty platform gross margin percentage, adjusted operating income, return on invested capital, net debt/ EBITDA, and the exclusion of corporate charges in certain calculations. Adjusted EPS 2006Y 2007Y 2008Y 2009Y 2010Y*** 2011Y*** 2012Y*** *Net Income attributable to PolyOne common shareholders $ 130.9 $ 40.9 $ (417.0) $ 106.7 $ 152.5 $ 153.4 $ 53.3 SunBelt equity earnings, after tax (68.5) (26.1) (20.8) (19.0) (14.7) (3.7) - Special items, after tax (21.2) 41.4 310.0 (31.0) 15.8 (30.5) 35.7 Tax adjustments (30.0) (30.7) 147.2 (44.9) (88.3) (42.3) 0.5 Adjusted net income $ 11.2 $ 25.5 $ 19.4 $ 11.8 $ 65.3 $ 76.9 $ 89.5 Diluted shares 92.8 93.1 92.7 93.4 96.0 94.3 89.8 Adjusted EPS $ 0.12 $ 0.27 $ 0.21 $ 0.13 $ 0.68 $ 0.82 $ 1.00 *** Restated results to exclude the Resin business.

Registered Drug Master File (DMF) / Device Master File (MAF)

Documented change control beyond CAS number and Registered Drug Master File (DMF)/Device Master File (MAF) documentation are common practices for the Mevopur portfolio.

To access Avient’s news library online, please visit www.avient.com/news # # # Investor Relations Contact: Giuseppe (Joe) Di Salvo Vice President, Treasurer and Investor Relations Avient Corporation +1 440-930-1921 giuseppe.disalvo@avient.com Media Contact: Kyle G. Three Months Ended September 30, Nine Months Ended September 30, Reconciliation to Consolidated Statements of Income 2022 2021 2022 2021 Sales $ 823.3 $ 818.0 $ 2,606.5 $ 2,508.5 Gross margin - GAAP 195.4 215.6 710.7 727.3 Special items in gross margin (Attachment 3) 31.8 17.3 35.6 27.7 Adjusted gross margin $ 227.2 $ 232.9 $ 746.3 $ 755.0 Adjusted gross margin as a percent of sales 27.7 % 28.5 % 28.6 % 30.1 % Operating income - GAAP 40.6 52.8 242.9 229.6 Special items in operating income (Attachment 3) 40.2 20.0 48.8 36.6 Adjusted operating income $ 80.8 $ 72.8 $ 291.7 $ 266.2 Adjusted operating income as a percent of sales 9.8 % 8.9 % 11.2 % 10.6 % The table below reconciles pre-special income tax expense and the pre-special effective tax rate to their most comparable US GAAP figures. Three Months Ended September 30, 2022 2021 GAAP Results Special Items Adjusted Results GAAP Results Special Items Adjusted Results (Loss) income from continuing operations before income taxes $ (29.0) $ 82.0 $ 53.0 $ 35.4 $ 19.9 $ 55.3 Income tax expense - GAAP 1.2 — 1.2 (2.0) — (2.0) Income tax impact of special items (Attachment 3) — (20.5) (20.5) — (4.6) (4.6) Tax adjustments (Attachment 3) — 6.8 6.8 — (3.6) (3.6) Income tax (expense) benefit $ 1.2 $ (13.7) $ (12.5) $ (2.0) $ (8.2) $ (10.2) Effective Tax Rate(1) 4.1 % 23.7 % 5.7 % 18.4 % (1) Rates may not recalculate from figures presented herein due to rounding 14 Nine Months Ended September 30, 2022 2021 GAAP Results Special Items Adjusted Results GAAP Results Special Items Adjusted Results Income from continuing operations before income taxes $141.2 $ 89.6 $ 230.8 $176.1 $ 36.5 $ 212.6 Income tax expense - GAAP (41.5) — (41.5) (32.1) — (32.1) Income tax impact of special items (Attachment 3) — (22.5) (22.5) — (8.9) (8.9) Tax adjustments (Attachment 3) — 10.8 10.8 — (1.6) (1.6) Income tax (expense) benefit $ (41.5) $ (11.7) $ (53.2) $ (32.1) $ (10.5) $ (42.6) Effective Tax Rate(1) 29.4 % 23.1 % 18.2 % 20.0 % (1) Rates may not recalculate from figures presented herein due to rounding Three Months Ended September 30, Nine Months Ended September 30, Reconciliation to EBITDA and Adjusted EBITDA: 2022 2021 2022 2021 Net (loss) income from continuing operations – GAAP $ (27.8) $ 33.4 $ 99.7 $ 144.0 Income tax (benefit) expense (1.2) 2.0 41.5 32.1 Interest expense 37.3 19.0 70.4 57.8 Depreciation and amortization from continuing operations 39.8 36.6 113.7 107.1 EBITDA $ 48.1 $ 91.0 $ 325.3 $ 341.0 Special items, before tax 82.0 19.9 89.6 36.5 Interest expense included in special items (10.0) — (10.0) — Depreciation and amortization included in special items (0.8) (0.9) (4.0) (0.1) Adjusted EBITDA $ 119.3 $ 110.0 $ 400.9 $ 377.4 NEWS RELEASE Attachment 1

Taxes, Fees, and Duties. Buyer will reimburse Seller for all central, state, provincial, local or other taxes (other than income taxes), excises or charges, including environmental remedial taxes and fees, which Seller must pay or account for, in connection with the manufacture and supply of Product, but only those amounts not already included in the price at the commencement of this contract. Buyer shall file all tax returns (wherever applicable) in a timely manner so as to enable Seller to be able to receive or set off from its tax liability, as the case may be, all tax credits (including input tax credits) available to Seller on account of the sale of the Products. 11.

The company also noted that it finished the year with cash flow from operations of $202 million; excluding $104 million of taxes paid on the sale of the Distribution business, cash flow from operations was $306 million. To access Avient’s news library online, please visit www.avient.com/news. Three Months Ended Year Ended Reconciliation of Pro Forma Adjusted Earnings per Share December 31, 2022 Net (loss) income from continuing operations attributable to Avient shareholders $ (17.0) $ 82.8 Special items, after tax (Attachment 3) 38.3 116.2 Amortization expense, after-tax (Attachment 1) 14.6 49.0 Adjusted net income from continuing operations excluding special items 35.9 248.0 APM pro forma adjustments to net income from continuing operations* 2.5 13.6 APM amortization expense, after tax* — 19.1 Pro forma adjusted net income from continuing operations attributable to Avient shareholders $ 38.4 $ 280.7 Weighted average diluted shares 91.7 92.2 Pro forma adjusted EPS - excluding special items $ 0.42 $ 3.04 * Pro forma adjustment for January - August 2022 APM results (period before Avient ownership) including the impacts of debt financing and prepayments on net income from continuing operations. 14 Free Cash Flow Calculation December 31, 2023 Cash provided by operating activities $ 201.6 Taxes paid on gain on sale of business 104.1 Adjusted cash provided by operating activities $ 305.7 Capital expenditures $ (119.4) Free cash flow $ 186.3 Three Months Ended March 31, 2023 Reconciliation to Condensed Consolidated Statements of Income $ EPS Net income from continuing operations attributable to Avient shareholders $ 20.8 $ 0.23 Special items, after tax 22.3 0.24 Amortization expense, after-tax 15.1 0.16 Adjusted net income / EPS $ 58.2 $ 0.63 Three Months Ended December 31, Year Ended December 31, Reconciliation to EBITDA and Pro Forma Adjusted EBITDA 2023 2022 2023 2022 Net income (loss) from continuing operations – GAAP $ 27.6 $ (16.6) $ 76.3 $ 83.1 Income tax (benefit) expense (7.0) (60.8) 11.0 (19.3) Interest expense 26.8 49.4 115.3 119.8 Depreciation and amortization from continuing operations 44.2 48.6 188.8 162.5 EBITDA from continuing operations $ 91.6 $ 20.6 $ 391.4 $ 346.1 Special items, before tax 22.4 104.3 114.6 194.0 Interest expense included in special items (0.1) (16.0) (2.3) (26.0) Depreciation and amortization included in special items — (1.5) (1.9) (5.5) Adjusted EBITDA $ 113.9 $ 107.4 $ 501.8 $ 508.6 APM pro forma adjustments - 8 months 2022* — — — 83.1 Pro forma adjusted EBITDA $ 113.9 $ 107.4 $ 501.8 $ 591.7 * Pro forma adjustment for January - August 2022 APM results (period before Avient ownership).

The comprehensive online publication highlights progress made toward Avient’s 2030 Sustainability Goals, along with other news and information on ESG matters. Three Months Ended June 30, Six Months Ended June 30, Reconciliation to Consolidated Statements of Income 2022 2021 2022 2021 Sales $ 1,302.4 $ 1,235.2 $ 2,596.2 $ 2,397.5 Gross margin - GAAP 303.8 288.7 597.5 591.1 Special items in gross margin (Attachment 3) (2.0) 12.6 3.8 10.4 Adjusted gross margin $ 301.8 $ 301.3 $ 601.3 $ 601.5 Adjusted gross margin as a percent of sales 23.3 % 24.4 % 23.2 % 25.1 % Operating income - GAAP 129.5 108.1 258.1 228.5 Special items in operating income (Attachment 3) 4.3 14.2 12.1 16.6 Adjusted operating income $ 133.8 $ 122.3 $ 270.2 $ 245.1 Adjusted operating income as a percent of sales 10.3 % 9.9 % 10.4 % 10.2 % The table below reconciles pre-special income tax expense and the pre-special effective tax rate to their most comparable US GAAP figures. Three Months Ended June 30, 2022 2021 GAAP Results Special Items Adjusted Results GAAP Results Special Items Adjusted Results Income from before income taxes $114.7 $ 3.4 $ 118.1 $ 89.8 $ 14.2 $ 104.0 Income tax expense - GAAP (30.0) — (30.0) (20.4) — (20.4) Income tax impact of special items (Attachment 3) — (0.8) (0.8) — (3.4) (3.4) Tax adjustments (Attachment 3) — 2.5 2.5 — 0.9 0.9 Income tax (expense) benefit $ (30.0) $ 1.7 $ (28.3) $ (20.4) $ (2.5) $ (22.9) Effective Tax Rate(1) 26.1 % 23.9 % 22.7 % 22.0 % (1) Rates may not recalculate from figures presented herein due to rounding 13 Six Months Ended June 30, 2022 2021 GAAP Results Special Items Adjusted Results GAAP Results Special Items Adjusted Results Income from before income taxes $225.8 $ 11.1 $ 236.9 $192.4 $ 16.6 $ 209.0 Income tax expense - GAAP (56.6) — (56.6) (43.3) — (43.3) Income tax impact of special items (Attachment 3) — (2.8) (2.8) — (4.3) (4.3) Tax adjustments (Attachment 3) — 4.0 4.0 — 2.0 2.0 Income tax (expense) benefit $ (56.6) $ 1.2 $ (55.4) $ (43.3) $ (2.3) $ (45.6) Effective Tax Rate(1) 25.0 % 23.4 % 22.5 % 21.8 % (1) Rates may not recalculate from figures presented herein due to rounding Reconciliation of EBITDA by Segment Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Operating income: Color, Additives and Inks $ 93.6 $ 86.3 $ 188.1 $ 175.1 Specialty Engineered Materials 36.6 37.3 76.3 71.5 Distribution 27.1 23.7 51.3 47.7 Corporate and eliminations (27.8) (39.2) (57.6) (65.8) Operating income $ 129.5 $ 108.1 $ 258.1 $ 228.5 Items below OI in Corporate: Other income, net $ 1.4 $ 1.2 $ 0.8 $ 2.7 Depreciation & amortization: Color, Additives and Inks $ 25.9 $ 25.3 $ 51.9 $ 52.6 Specialty Engineered Materials 7.7 8.1 15.5 15.9 Distribution 0.2 0.2 0.4 0.4 Corporate and eliminations 2.7 0.2 6.5 2.0 Depreciation & Amortization $ 36.5 $ 33.8 $ 74.3 $ 70.9 EBITDA: Color, Additives and Inks $ 119.5 $ 111.6 $ 240.0 $ 227.7 Specialty Engineered Materials 44.3 45.4 91.8 87.4 Distribution 27.3 23.9 51.7 48.1 Corporate and eliminations (25.1) (39.0) (51.1) (63.8) Other income, net 1.4 1.2 $ 0.8 $ 2.7 EBITDA $ 167.4 $ 143.1 $ 333.2 $ 302.1 14 Three Months Ended June 30, Six Months Ended June 30, Reconciliation to EBITDA and Adjusted EBITDA: 2022 2021 2022 2021 Net income – GAAP $ 84.7 $ 69.4 $ 169.2 $ 149.1 Income tax expense 30.0 20.4 56.6 43.3 Interest expense 16.2 19.5 33.1 38.8 Depreciation and amortization 36.5 33.8 74.3 70.9 EBITDA $ 167.4 $ 143.1 $ 333.2 $ 302.1 Special items, before tax 3.4 14.2 11.1 16.6 Depreciation and amortization included in special items (1.1) 1.4 (3.2) 0.8 Adjusted EBITDA $ 169.7 $ 158.7 $ 341.1 $ 319.5 Three Months Ended June 30, 2021 Reconciliation to Condensed Consolidated Statements of $ EPS Net income attributable to Avient shareholders $ 68.8 $ 0.74 Special items, after tax (Attachment 3) 11.7 0.13 Adjusted net income / EPS - excluding special items 80.5 0.87 FX adjustment (4.9) (0.05) Adjusted net income / EPS - excluding special items, adjusted for FX $ 75.6 $ 0.82 NEWS RELEASE Attachment 1