Results of Operations

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of Earliest Event Reported): May 7, 2026 Magnera Corporation (Exact name of registrant as specified in its charter) Pennsylvania   001-03560   23-0628360 (State or other jurisdiction of incorporation)   (Commission File Number)   (I.R.S. Employer Identification No.) 9335 Harris Corners Pkwy , Ste 300 , Charlotte , North Carolina 28269 (Address of principal executive offices) (Zip Code) Registrant’s telephone number, including area code: 866 744-7380 (N/A) Former name or former address, if changed since last report Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:   ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Title of each class   Trading Symbol(s)   Name of each exchange on which registered Common Stock   MAGN   New York Stock Exchange Indicate by check mark whether the registrant is an emerging growth company in as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company  ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐ Item 2.02 Results of Operations and Financial Condition. On May 7, 2026, the Company reported its results of operations for the quarter ended March 28, 2026. A copy of the press release issued by the Company is furnished herewith as Exhibit 99.1. Item 9.01 Financial Statements and Exhibits. d) Exhibits. 99.1 Press release issued May 7, 2026. 104 Cover Page Interactive Data File (embedded within the Inline XBRL document). The information furnished in this Current Report on Form 8-K and Exhibit 99.1 attached hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Magnera Corporation May 7, 2026 By: /s/ James M. Till James M. Till Chief Financial Officer