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: 2025年10月31日 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.

Vents 1. Draft 1. Draft angle should be 1/2° to 1° per side.

Runners 1. Cold Slug Wells 1. Vents 1.

Raportowanie schematów podatkowych Spółka w roku 2022 nie przekazała informacji o schematach podatkowych, o których mowa w art. 86a § 1 pkt 10 Ordynacji podatkowej. Charakter transakcji Strona transakcji 1. transakcja towarowa sprzedaż Nierezydent 2. 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.

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. Charakter transakcji Strona transakcji 1. transakcja towarowa sprzedaż Nierezydent 2. 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.

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. Avient 2011 and 2018 valuations reflect trailing 12 months EBITDA at December 31 of the respective years. 37 EV / 2023E EBITDA Historic Multiple 6.5 8.3 9.9 14.6 13.7 13.0 11.9 8.8 18.7 17.4 11.8 10.0 9.7 9.1 8.0 7.9 A vi e n t (2 0 1 1 ) A vi e n t (2 0 1 8 ) A vi e n t (2 0 2 3 ) K W R P P G R P M A V Y F U L E C L H X L F M C A S H S C L C E E M N H U N 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.

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. Avient 2011 and 2018 valuations reflect trailing 12 months EBITDA at December 31 of the respective years. 33 EV / 2023E EBITDA Historic Multiple 6.5 8.3 9.9 14.6 13.7 13.0 11.9 8.8 18.7 17.4 11.8 10.0 9.7 9.1 8.0 7.9 A vi e n t (2 0 1 1 ) A vi e n t (2 0 1 8 ) A vi e n t (2 0 2 3 ) K W R P P G R P M A V Y F U L E C L H X L F M C A S H S C L C E E M N H U N 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.

Handelsregisteramt des Kantons Basel-Landschaft BASEL LAN DSCHAFT $t Firmennummer cHE-480.567.505 Rechtsnatur Aktiengesellschaft Eintragung 09.09.2019 Löschung U be rtra g CH-280.3.023.7 7 7 -6 von: auf: 1 llillllll llll ll illllll lll A e E n'rasunsen Ei Lö Firma Rel Sitz 1 I 7 7 7 7 Avient Colorants Switzerland AG (Avient Colorants Switzerland Ltd) 1 Muttenz Ei Lö Aktienkapital (CHF) Liberierung (CHF) Aktien-Stückelung Ei Lö Domiziladresse 1 100'000.00 100'000.00 100 vinkulierte Namenaktien zu CHF 1'000.00 1 Rothausstrasse 61 4132 Muttenz Ei Lö Zweck Ei Lö weitere Adressen 1 Die Gesellschaft bezweckt den Erwerb, die Ver"waltung und Veräusserung von Beteiligungen an Unternehmen, die auf dem Gebiet der Chemie und verwandten Gebieten tätig sind, insbesondere im Bereich Masterbatches und Kunststoffe. Ei Lö Bemerkungen Rel Statutendatum 1 1 Die Ubertragbarkeit der Namenaktien ist nach Massgabe der Statuten beschränkt. Seite / ld 1 2 3 4 4265 6095 31 55 3230B 09.09.2019 12.12.2019 23.06.2020 25.06.2020 176 244 122 124 12.O9.2019 17.12.2019 26.06.2020 30.06.2020 1004714735 1 004785379 1 004921 598 1004924109 5 6 7 3929 4022 6230 B 03.08.2020 07.08.2020 01.12.2024 151 15s (( B 06.08.2020 12.08,2020 ienehmigung 1 004952966 1 004956361 HRA) Ei Ae Lö Personalangaben Funktion Zeichnungsart 1 1 1 I 1 1 1 1 2 2 2 2 3 3 3 3 3 3 3 3 3m 3m 3 @inCen ffiin;in-*esefleH PricewaterhouseCoopers AG (CH E-393 .441 .652), in Basel ffiingen ingen ft4erkle,in;+'{grbe ;,rigefi in-ffiden Ufui+ermann-,+t l:M-des \tenvaHungtsrates l#itgffies llenva}tungsrates tlitglie#es Venwattungsrates Revisionsstelle ffiien ffiien ffiien 1(offiien ffieien ffiien ffiien ldlektivuntersehrift-z*zweien ffiien ffiien ffiien Adesheim, 02.12.2020 1 1 :46 Fortsetzung auf der folgenden Seite Handelsregisteramt des Kantons Basel-Landschaft BAS E Li!

The company noted that full year 2024 GAAP EPS includes special items of $0.17 (see attachment 3) and $0.65 of intangible amortization expense (see attachment 1). Organic sales grew in all geographic regions with the U.S. and Canada growing at 6%, EMEA at 1%, Asia at 7% and Latin America at 14%.”2 Commenting on full year 2024 results, Dr. You are advised to consult any further disclosures we make on related subjects in our reports on Form 10-Q, 8-K and 10-K that we provide to the Securities and Exchange Commission. 6 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.