Certificate of Registration 9001:2015 MSP 9001:2015–MSP-ANAB-US (2.0) Page 1 of 2 Certificate of Registration of Quality Management System to ISO 9001:2015 The National Standards Authority of Ireland certifies that: Colorant Chromatics Ab Kroklundsvagen 346 AX-22 320 Odkarby Aland Finland has been assessed and deemed to comply with the requirements of the above standard in respect of the scope of operations given below: The Design, Manufacture and Sales of Fluoropolymer Color Concentrates and Compounds Additional sites covered under this multi-site certification are listed on the Annex (File No. 19.2540/C) Approved by: Geraldine LarkinChief Executive Officer Approved by: Lisa Greenleaf Operations Manager Registration Number: 19.2540/C Certification Granted: May 15, 1997 Effective Date: Oct 20, 2018 Expiry Date: Oct 19, 2021 National Standards Authority of Ireland, 20 Trafalgar Square, Nashua, New Hampshire, NH 03063, USA T +1 603 882 4412 9001:2015–MSP-ANAB-US (2.0) Page 2 of 2 Annex to Certificate Number: 19.2540/C Scope of Registration: The Design, Manufacture and Sales of Fluoropolymer Color Concentrates and Compounds Activity Location Central Management Group, Design, Manufacture Colorant Chromatics Kroklundsvagen 346 AX-22 320 Odkarby Aland Finland File No.: 19.2540/C Headquarters, Sales, Distribution Colorant Chromatics Europe B.V. Hastelweg 269 - 273 NL-5652 CV Eindhoven The Netherlands File No.: 19.2540/B Sales, Distribution Colorant GmbH Justus-Staudt-Strasse 1 Limburg-Offheim Germany 65555 File No.: 19.2540/A Design, Manufacture, Sales, Distribution Chromatics, Inc. 19 Francis J.

Date Of Certification: 11 December 2024 Date Of Expiration: 10 December 2027 IATF Certificate N°: 0558656 Bureau Veritas Certification Certificate No: FR094003 - IATF Revision: 1 For Bureau Veritas Certification Holding, Tour ALTO, 4 place des saisons, 92400 COURBEVOIE – France (The official document is in English. Any translations of this document shall be used for reference only.) 1/2 Certificate of Approval AWARDED TO PolyOne France Tossiat Route de la vavrette, 01250, Tossiat - France IATF USI: LWZS4P Bureau Veritas Certification certify that the Quality Management System of the above organisation has been audited and found to be in accordance with the requirements of IATF 16949 - FIRST EDITION and the applicable customer specific requirements SCOPE Design and manufacturing PERMITTED EXCLUSION(S) None PRODUCT(S) DELIVERED colour with additive concentrates for thermoplastic resins and speciality compounds obtained by mixing and extrusion https://e-cer.bureauveritas.com/68LJQE0ZV0CO6I7YW0YSXOUMV9WWROQPHPI2AOHRRLFFVRAVTFVZGXKWIE3TOWLTTKEWCPQB9UNAPXHH6T0HXOMUEDVYPRPJLEXBBTKQYPBRICYOKY143TECQ5UMHGA3JX Date Of Certification: 11 December 2024 Date Of Expiration: 10 December 2027 IATF Certificate N°: 0558656 Bureau Veritas Certification Certificate No: FR094003 - IATF Revision: 1 For Bureau Veritas Certification Holding, Tour ALTO, 4 place des saisons, 92400 COURBEVOIE – France (The official document is in English.

1400 Ravello Drive, Katy, TX, 77449-5164, USA - TEL: +1 281-396-1000. www.dnv.com Page 1 of 2 MANAGEMENT SYSTEM CERTIFICATE Certificate no.: 11229-2006-CHN-IATF IATF Certificate No: 0573810 Valid: 21 May 2025 – 20 May 2028 This is to certify that the management system of PolyOne - Suzhou, China EM Sector, 77 Shenggang Street, Suzhou Industrial Park, Suzhou, Jiangsu, China 215024 (USI: CF4943) and, if applicable, the remote supporting locations as mentioned in the Appendix accompanying this Certificate has been found to conform to the Quality Management System standard: IATF 16949:2016 This certificate is valid for the following scope: DESIGN AND MANUFACTURE OF PLASTIC COMPOUNDING MATERIAL EXCLUSION: NONE http://www.dnv.com Certificate no.: 11229-2006-CHN-IATF IATF Certificate No: 0573810 Place and date: Katy, TX, 22 May 2025 Lack of fulfilment of conditions as set out in the Certification Agreement may render this Certificate invalid. ACCREDITED UNIT: DNV Business Assurance USA Inc., 1400 Ravello Drive, Katy, TX, 77449-5164, USA - TEL: +1 281-396-1000. www.dnv.com Page 2 of 2 Appendix to Certificate PolyOne - Suzhou, China Remote Support Locations included in the certification are as follows: Site Name Site Address RSL Activities Certification Body Avient China Co., Ltd.

www.fojas.cl Pag: 1/1 Pag: 1/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 2/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 3/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 4/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 5/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 6/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 7/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 8/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 9/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 10/11 Certificado Nº 123456880196 Verifique validez en http://www.fojas.cl Pag: 11/11 2021-05-31T12:52:48-0400 Santiago - Chile EDUARDO JAVIER DIEZ MORELLO Notario Publico Eduardo_Diez_Morello

No. 0562.01) 11/30/2023 Page 1 of 1 SCOPE OF ACCREDITATION TO ISO/IEC 17025:2017 AVIENT CORPORATION 733 East Water Street North Baltimore, OH 45872 Claire Holman Phone: (419) 257-1327 MECHANICAL Valid To: October 31, 2025 Certificate Number: 0562.01 In recognition of the successful completion of the A2LA evaluation process, accreditation is granted to this laboratory to perform the following automotive plastics tests: Test Method: Test Name: ASTM D412 Tensile ASTM D523 Specular Gloss ASTM D618 (A) Conditioning of Plastics ASTM D624 (Die C) Tear Strength ASTM D638 Tensile Properties ASTM D792 (A) Density and Specific Gravity by Displacement ASTM D1004 Initial Tear Resistance ASTM D1203 (A) Volatile Loss ASTM D1895 (A) Apparent Density, Bulk Factor, Pourability ASTM D1921 Particle Size (Sieve Analysis) ASTM D2240 Durometer Hardness (Shore A and D) ASTM E1331 Color by Spectrophotometry Using Hemispherical Geometry FMVSS 571.302 Flammability FORD BN-102-01 (A) Low Temperature Flexibility FORD BO-131-03 Interior Odor ISO 3795 Determination of Burning Behavior of Interior Materials SAE J323 (A) Cold Cracking (Mandrel Bend) SAE J1351 Hot Odor for Insulation Materials SAE J1545 Instrumental Color Difference Measurement DOC-058151 Angle of Repose 1 Laboratory Developed Method For the tests to which this accreditation applies, please refer to the laboratory’s Mechanical Scope of Accreditation.

& Canada EMEA Asia Latin America 64% 36% Specialty Engineered Materials Color Additives and Inks 41% 36% 18% 5% 7% 7% 23% 19% 9% 16% 10% 5% 4% Defense Healthcare Packaging Consumer Building & Construction Industrial Transportation Energy Telecom Geography Segment Industry 2024 Financial Guidance $525 to $530 million Adjusted EBITDA $2.63 to $2.67 Adjusted EPS 4 Industry Sustainability Standards ESG Ratings Performance 1 2 4 87th 94th percentile Avient CDP Score: A- SUSTAINABILITY PERFORMANCE AND RECOGNITION O CTO BE R 3 1 , 2024 W EB CAS T P RE SE N TATI O N 6 Q3 2024 HIGHLIGHTS • 8.5% organic sales growth driven by broad-based growth across all regions and most end markets in both CAI and SEM segments • Growth stemmed from gaining share, winning new product specifications and restocking in certain end markets • Both segments expanded YoY EBITDA margins by 40 bps each • Adjusted EPS of $0.65, an increase of 14% vs the prior year • Successfully refinanced $650M outstanding senior notes due 2025; extending maturity to 2031 • Increased dividend 5% to $1.08 on an annualized basis; 14th consecutive increase Adj. FX +8.5% FX -0.4% Total Avient +8.1% Note: Regional Sales Percentages exclude impact of foreign exchange COLOR, ADDITIVES & INKS SEGMENT (Q3 2024 PERFORMANCE VS Q3 2023) $487 $522 Q3 23 Q3 24 $89 $97 Q3 23 Q3 24 Sales Adjusted EBITDA (in millions) (in millions) Sales Adjusted EBITDA 10 + 7% (+8% excluding FX) + 9% (+11% excluding FX) 18.3% +40 bps *18.7% * * Adjusted EBITDA Margin % • Sales growth driven by winning new product specifications in consumer & packaging, strong underlying demand in healthcare and improving demand in building & construction • Favorable mix and raw material deflation contributed to EBITDA margin expansion SPECIALTY ENGINEERED MATERIALS SEGMENT (Q3 2024 PERFORMANCE VS Q3 2023) $268 $295 Q3 23 Q3 24 $51 $57 Q3 23 Q3 24 Sales Adjusted EBITDA (in millions) (in millions) Sales Adjusted EBITDA 11 • Sales growth driven by restocking in healthcare & consumer end markets and strong underlying demand for composite applications used in building & construction, energy and defense end markets • Favorable mix contributed to EBITDA margin expansion + 10% (+10% excluding FX) + 12% (+13% excluding FX) 19.0% +40 bps *19.4% * * Adjusted EBITDA Margin % 2024 G U IDA N CE FY 2024 GUIDANCE Previous (Aug 6) Current Adjusted EPS $2.55 to $2.70 $2.63 to $2.67 Adjusted EBITDA $515 to $540 million $525 to $530 million Interest Expense $105 million $104 million Adjusted Effective Tax Rate 23% to 25% 23% to 25% Capital Expenditures & Investment in S/4 Hana ~$140 million ~$140 million 13 14 • Investor Day to be held December 4, 2024 at the NYSE, beginning at 10AM • The focus will be to do a deep dive on the Company’s strategy • Registration available at www.avient.com/investors 2024 AVIENT INVESTOR DAY AP P EN D IX 17 Performance Additives 15% Pigments 13% TiO2 9% Dyestuffs 2% Polyethylene 10%Nylon 5% Polypropylene 4% Styrenic Block Copolymer 4% Other Raw Materials 38% ~40% hydrocarbon based (Grey shaded materials are hydrocarbon based, includes portion of “Other Raw Materials”) Non-hydrocarbon based materials RAW MATERIAL BASKET SEGMENT DATA U.S. & Canada 41% EMEA 36% Asia 18% Latin America 5% 2023 SEGMENT, END MARKET AND GEOGRAPHY GEOGRAPHY REVENUESEGMENT FINANCIALS Consumer 19% Packaging 23%Industrial 16% Building and Construction 9% Telecommunications 4% Energy 5% Defense 7% END MARKET REVENUE $2,007M $358M $1,138M $224M Sales EBITDA Specialty Engineered Materials Color Additives and Inks $502M$3,143M (1) Transportation 10% Healthcare 7% 19 (1) Total company sales and adjusted EBITDA of $3,143M and $502M, respectively, include intercompany sales eliminations and corporate costs 2023 REVENUE | $2 .0 B ILL ION US & Canada 34% EMEA 37% Asia 21% Latin America 8% END MARKET REGION 20 Packaging 34% Consumer 21% Healthcare 8% Industrial 15% Transportation 9% Building & Construction 10% Telecommunications 1% Energy 2% COLOR, ADDITIVES & INKS 2023 REVENUE | $1 .1 B ILL ION US & Canada 52% EMEA 35% Asia 13% 21 Packaging 5% Consumer 16% Healthcare 6%Industrial 16% Transportation 12% Telecommunications 9% Energy 10% Defense 18% Building & Construction 8% END MARKET REGION SPECIALTY ENGINEERED MATERIALS Packaging 32% Consumer 26% Healthcare 9% Industrial 13% Building & Construction 6% Telecommunications 2% Energy 2% Defense 1% Asia (18% of sales) Transportation 9% 2023 AVIENT REGIONAL SALES Packaging 25% Consumer 13% Healthcare 5% Industrial 18% Building & Construction 9% Energy 5% Defense 8% EMEA (36% of sales)Transportation 13% Packaging 13% Consumer 22% Healthcare 10% Industrial 16% Building & Construction 12% Energy 6% Defense 8% US & Canada (41% of sales) Transportation 9% Packaging 59% Consumer 22% Healthcare 2% Industrial 8% Building & Construction 4% LATAM (5% of sales) Transportation 5% Telecommunications 4% Telecommunications 4% 22 BY END MARKET Reconciliation of Non-GAAP Financial Measures (Unaudited) (Dollars in millions, except for per share data) Senior management uses comparisons of adjusted net income from continuing operations attributable to Avient shareholders and diluted adjusted earnings per share (EPS) from continuing operations attributable to Avient shareholders, excluding special items, to assess performance and facilitate comparability of results. Three Months Ended September 30, 2024 2023 Reconciliation to Condensed Consolidated Statements of Income $ EPS(1) $ EPS(1) Net income from continuing operations attributable to Avient shareholders $ 38.2 $ 0.41 $ 5.1 $ 0.06 Special items, after-tax 6.6 0.07 32.0 0.35 Amortization expense, after-tax 15.0 0.16 15.2 0.16 Adjusted net income / EPS $ 59.8 $ 0.65 $ 52.3 $ 0.57 (1) Per share amounts may not recalculate from figures presented herein due to rounding Three Months Ended September 30, Reconciliation to EBITDA and Adjusted EBITDA: 2024 2023 Net income from continuing operations – GAAP $ 38.7 $ 5.1 Income tax expense (benefit) 11.3 (0.1) Interest expense, net 26.9 30.3 Depreciation & amortization 45.1 46.4 EBITDA from continuing operations $ 122.0 $ 81.7 Special items, before tax 9.7 43.2 Interest expense included in special items (1.3) (2.2) Depreciation & amortization included in special items (0.4) — Adjusted EBITDA $ 130.0 $ 122.7 Adjusted EBITDA as a percent of sales 15.9 % 16.3 % 1 Three Months Ended September 30, 2024 2023 Sales: Color, Additives and Inks $ 521.5 $ 486.5 Specialty Engineered Materials 294.6 267.9 Corporate (0.9) (0.7) Sales $ 815.2 $ 753.7 Operating income: Color, Additives and Inks $ 75.5 $ 64.5 Specialty Engineered Materials 36.4 30.3 Corporate (34.7) (60.5) Operating income $ 77.2 $ 34.3 Depreciation & amortization: Color, Additives and Inks $ 21.9 $ 24.6 Specialty Engineered Materials 20.7 20.5 Corporate 2.5 1.3 Depreciation & amortization $ 45.1 $ 46.4 Earnings before interest, taxes, depreciation and amortization (EBITDA): Color, Additives and Inks $ 97.4 $ 89.1 Specialty Engineered Materials 57.1 50.8 Corporate (32.2) (59.2) Other (expense) income, net (0.3) 1.0 EBITDA from continuing operations $ 122.0 $ 81.7 Special items, before tax 9.7 43.2 Interest expense included in special items (1.3) (2.2) Depreciation & amortization included in special items (0.4) — Adjusted EBITDA $ 130.0 $ 122.7 Adjusted EBITDA as a percent of sales: Color, Additives and Inks 18.7 % 18.3 % Specialty Engineered Materials 19.4 % 19.0 % 2 Year Ended December 31, 2023 Reconciliation to Condensed Consolidated Statements of Income $ EPS Net income from continuing operations attributable to Avient shareholders $ 75.8 $ 0.83 Special items, after-tax 79.3 0.86 Amortization expense, after-tax 61.5 0.67 Adjusted net income / EPS $ 216.6 $ 2.36 Adjusted Free Cash Flow Calculation December 31, 2023 Cash provided by operating activities $ 201.6 Capital expenditures (119.4) Free cash flow 82.2 Taxes paid on gain on sale of business 104.1 Adjusted free cash flow $ 186.3 Year Ended December 31, 2023 Sales: Color, Additives and Inks $ 2,007.4 Specialty Engineered Materials 1,138.2 Corporate (2.8) Sales $ 3,142.8 Operating income: Color, Additives and Inks $ 259.9 Specialty Engineered Materials 142.5 Corporate (205.6) Operating income $ 196.8 Depreciation & amortization: Color, Additives and Inks $ 98.3 Specialty Engineered Materials 81.5 Corporate 9.0 Depreciation & amortization $ 188.8 Earnings before interest, taxes, depreciation and amortization (EBITDA): Color, Additives and Inks $ 358.2 Specialty Engineered Materials 224.0 Corporate (196.6) Other income, net 5.8 EBITDA from continuing operations 391.4 Special items, before tax 114.6 Interest expense included in special items (2.3) Depreciation & amortization included in special items (1.9) Adjusted EBITDA $ 501.8 Adjusted EBITDA as a percent of sales 16.0 % 3 Avient M11 Investor Presentation.pdf IR Deck - AVNT-2024.09.30 (M11) - 11.05.24 11AM.pdf Attachment

Avient acquired the Clariant Masterbatch business (CMB) on July 1, 2020 (the “Acquisition Date”). Clariant MB acquired July 1, 2020 COLORWORKS INSPIRATION. Operating Income $3,783 $4,300 2020PF 2021E Adjusted EPS (1) Financial information is pro forma to include a full year of Clariant Masterbatch business acquisition Previous Guidance Current Guidance $3,783 $4,650 2020PF 2021E $308 $410 2020PF 2021E $308 $430 2020PF 2021E $1.93 $2.80 2020PF 2021E $1.93 $3.00 2020PF 2021E (1) (1)(1) (1)(1) (1) (in millions) (in millions) $442 $457 $580 2019PF 2020PF 2021E $1.74 $1.93 $3.00 2019PF 2020PF 2021E FULL YEAR 2019 – 2021 ORGANIC GROWTH (TOTAL COMPANY) 16 Sales Adjusted EBITDA $3,981 $3,783 $4,650 2019PF 2020PF 2021E + 17% Adjusted EPS (1) Financial information is pro forma to include a full year of Clariant Masterbatch business acquisition (1) (1) (in millions) (in millions) (1)(1) + 31% + 72% (1) (1) ($ in millions) 2021E Adjusted EBITDA 580$ Free Cash Flow 280$ Total Debt 1,860 Less: Cash (755) Net Debt 1,105$ 2021E Net Debt / Adjusted EBITDA 1.9x 17 BALANCE SHEET • Acquisition of Magna Colours completed on July 1 – expands sustainable solutions portfolio through water-based inks technology • Deleveraging to 1.9x net debt to adjusted EBITDA by the end of 2021 • Driven by record adjusted EBITDA performance and strong free cash flow generation from asset light business • Future cash deployment: M&A, opportunistic share repurchases and balance sheet / continued leverage reduction 3.5x 2.7x 1.9x 2019PF 2020PF 2021E Net Debt / Adjusted EBITDA (1) (1) (1) Financial information is pro forma to include a full year of Clariant Masterbatch business acquisition SUSTAINABILITY FOR A BETTER TOMORROW 18 • Revenue from sustainable solutions expected to grow 14% in 2021 as our innovation efforts and collaboration with customers continues to accelerate • Investments centered around innovation and global sustainability megatrends o Enabling a circular economy – Technologies that allow for increased use of post-consumer recycled (PCR) material and improve recyclability of plastics o Light-weighting – Composites and CAI applications to reduce weight and material requirements, which minimize energy and carbon emissions o Eco-Conscious – Health and human safety applications as well as Avient’s alternative materials to replace lead, PVC, halogens, BPA and other less eco-friendly options 18 2016 2017 2018 2019 2020PF** Bio-polymers Reduced Energy Use Human Health & Safety Sustainable Infrastructure VOC Reduction Recycle Solutions Eco-Conscious Lightweighting Revenue From Sustainable Solutions* 2016-2020 $405M $455M *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 Masterbatch business $340M $550M $790M 18 19 Key Updates • Includes Clariant Masterbatch performance • Increases disclosures and ESG data • Provides performance updates on 2030 Sustainability Goals • Commits to operational carbon neutrality in 2050 and 100% renewable energy by 2050 (RE 100) • Announces Avient’s participation in U.N.

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To participate in the audio-only portion of the call, dial 1-844-835- 7433 (domestic) or 1-914-495-8589 (international) and provide conference ID number 4774915. To listen to this recording, dial 1-855-859- 2056 (domestic) or 1-404-537-3406 (international) and provide conference ID number 4774915. Rose Vice President, Corporate Communications Avient Corporation +1 440-930-3162 kyle.rose@avient.com mailto:giuseppe.disalvo@avient.com mailto:kyle.rose@avient.com NEWS RELEASE

Raportowanie schematów podatkowych Spółka w roku 2023 nie przekazała informacji o schematach podatkowych, o których mowa w art. 86a § 1 pkt 10 Ordynacji podatkowej. Informacje o złożonych przez podatnika wnioskach o wydanie ogólnej interpretacji podatkowej, o której mowa w art. 14a § 1 Ordynacji podatkowej (art. 27c ust. 2 pkt 4a CIT Akt) Spółka w roku 2023 nie złożyła wniosku o wydanie ogólnej interpretacji podatkowej. Informacje o złożonych przez podatnika wnioskach o wydanie wiążącej informacji akcyzowej, o której mowa w art. 7d ust. 1 ustawy o podatku akcyzowym (art. 27c ust. 2 pkt 4d CIT Akt) Spółka w roku 2023 nie złożyła wniosku o wydanie wiążącej informacji akcyzowej.