Full Year Comparisons Pro Forma for Acquisition of Clariant’s Color Business The company acquired Clariant’s color (“Clariant Color”) business on July 1, 2020 (the “Acquisition Date”). 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 2171339. 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.

Runners 1. Cold Slug Wells 1. Vents 1.

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.

Raportowanie schematów podatkowych Spółka w roku 2022 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 2022 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 2022 nie złożyła wniosku o wydanie wiążącej informacji akcyzowej.

PRODUCT BULLETIN PROPERTY COMPARISON TRILLIANT HC VS NYLON Density Impact Flexural Modulus (Dry) Tensile Strength (Dry) HDT Equilibrium Moisture — PKE-GF PA12-GF PA612-GF 5 4 3 2 1 0 Impact Shrink Flexural Modulus (Dry) Chemical Resistance Flexural Modulus (Cond.) CO2 Emission Factor — Trilliant HC — PA6-GF — PA66-GF HDT Wear Density 5 4 3 2 1 0 Equilibrium Moisture 1: Poor 3: Good 5: Excellent Density Impact Flexural Modulus (Dry) Tensile Strength (Dry) HDT Equilibrium Moisture — PKE-GF PA12-GF PA612-GF 5 4 3 2 1 0 Impact Shrink Flexural Modulus (Dry) Chemical Resistance Flexural Modulus (Cond.) CO2 Emission Factor — Trilliant HC — PA6-GF — PA66-GF HDT Wear Density 5 4 3 2 1 0 Equilibrium Moisture 1: Poor 3: Good 5: Excellent 1.844.4AVIENT www.avient.com Copyright © 2023, Avient Corporation.

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.

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.

Pro Forma Financial Information The Company acquired Avient Protective Materials (“Dyneema”) on September 1, 2022 (the “Acquisition Date”) and sold the Distribution segment on November 1, 2022. To provide comparable results, the company references “pro forma” financial metrics, which include the business results of Avient Protective Materials for periods prior to the Acquisition Date, as if the transaction occurred on January 1, 2021 and reflect Distribution as a discontinued operation. Three Months Ended December 31, 2023 2022 Reconciliation to Condensed Consolidated Statements of Income $ EPS(1) $ EPS(1) Net income (loss) from continuing operations attributable to Avient shareholders $ 27.8 $ 0.30 $ (17.0) $ (0.19) Special items, after tax (Attachment 3) 5.4 0.06 38.3 0.42 Amortization expense, after-tax 15.0 0.16 14.6 0.16 Adjusted net income / EPS $ 48.2 $ 0.52 $ 35.9 $ 0.39 (1) Per share amounts may not recalculate from figures presented herein due to rounding Year Ended December 31, 2023 2022 Reconciliation to Condensed Consolidated Statements of Income $ EPS(1) $ EPS(1) Net income from continuing operations attributable to Avient shareholders $ 75.8 $ 0.83 $ 82.8 $ 0.90 Special items, after tax (Attachment 3) 79.3 0.86 116.2 1.26 Amortization expense, after-tax 61.5 0.67 49.0 0.53 Adjusted net income / EPS $ 216.6 $ 2.36 $ 248.0 $ 2.69 (1) Per share amounts may not recalculate from figures presented herein due to rounding 1 Three Months Ended December 31, Year Ended December 31, Reconciliation to EBITDA and Pro Forma Adjusted EBITDA 2023 2022 2023 2022 Sales - GAAP $ 719.0 $ 790.4 $ 3,142.8 $ 3,396.9 Pro forma APM adjustments — — — 256.1 Pro forma adjusted sales $ 719.0 $ 790.4 $ 3,142.8 $ 3,653.0 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 adjusted EBITDA as a percent of sales 15.8 % 13.6 % 16.0 % 16.2 % * Pro forma adjustment for January - August 2022 APM results (period before Avient ownership).