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kn-202602050001587523false00015875232026-02-052026-02-05

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): February 5, 2026

Knowles Corporation (Exact name of registrant as specified in its charter)

Delaware001-3610290-1002689 (State or Other Jurisdiction of Incorporation)(Commission File Number)(I.R.S. Employer Identification No.)

1151 Maplewood Drive, Itasca, IL (Address of Principal Executive Offices)

60143 (Zip Code)

Registrant's telephone number, including area code: (630) 250-5100 (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 classTrading symbolName of each exchange on which registered Common stock, $0.01 par value per shareKNNew York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company 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 February 5, 2026, Knowles Corporation issued a press release announcing its results of operations for the year and quarter ended December 31, 2025 and posted on its website at http://investor.knowles.com presentation slides which summarize certain of its results of operations for the year and quarter ended December 31, 2025. Knowles Corporation's quarterly financial conference call and webcast will be held on February 5, 2026. A copy of the press release is being furnished as Exhibit 99.1 hereto and a copy of the presentation slides is being furnished as Exhibit 99.2 hereto.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

The following exhibits are furnished as part of this report: Exhibit NumberDescription

99.1 Press Release of Knowles Corporation dated February 5, 2026.

99.2

Presentation Slides dated February 5, 2026.

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

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.

KNOWLES CORPORATION

Date:February 5, 2026By: /s/ Robert J. Perna Robert J. Perna Senior Vice President, General Counsel & Secretary

kn-202510230001587523FALSE00015875232025-10-232025-10-23

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): October 23, 2025

Knowles Corporation (Exact name of registrant as specified in its charter)

Delaware001-3610290-1002689

(State or Other Jurisdiction of Incorporation)(Commission File Number)(I.R.S. Employer Identification No.)

1151 Maplewood Drive, Itasca, IL (Address of Principal Executive Offices)

60143 (Zip Code)

Registrant's telephone number, including area code: (630) 250-5100 (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 classTrading SymbolName of each exchange on which registered Common Stock, $0.01 par value per shareKNNew York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company 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. o

Item 2.02 Results of Operations and Financial Condition.

On October 23, 2025, Knowles Corporation (the "Company") issued a press release announcing its results of operations for the quarter ended September 30, 2025 and posted on its website at http://investor.knowles.com presentation slides which summarize certain of its results of operations for the quarter ended September 30, 2025. Knowles Corporation's quarterly financial conference call and webcast will be held on October 23, 2025. A copy of the press release is being furnished as Exhibit 99.1 hereto and a copy of the presentation slides is being furnished as Exhibit 99.2 hereto.

The information furnished with the Current Report on Form 8-K and the related exhibits included in Item 9.01 shall not be deemed to be "filed" for purposes 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 expressly set forth by specific reference in such filing.

Forward Looking Statements

This Current Report on Form 8-K contains forward-looking statements within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995, such as statements relating to the expected impact of the Company's restructuring program, including estimates of timing and amounts of restructuring charges. The words “believe,” “expect,” “anticipate,” “project,” “estimate,” “budget,” “continue,” “could,” “intend,” “may,” “plan,” “potential,” “predict,” “seek,” “should,” “will,” “would,” “objective,” “forecast,” “goal,” “guidance,” “outlook,” “effort,” “target,” and similar expressions, among others, generally identify forward-looking statements, which speak only as of the date the statements were made. The statements in this Current Report on Form 8-K are based on currently available information and the current expectations, forecasts, and assumptions of Knowles’ management concerning risks and uncertainties that could cause actual outcomes or results to differ materially from those outcomes or results that are projected, anticipated, or implied in these statements, including risks, relevant factors, and uncertainties identified in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, subsequent Reports on Forms 10-Q and 8-K and our other filings we make with the U.S. Securities and Exchange Commission. The Company disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

The following exhibits are furnished as part of this report: Exhibit NumberDescription

99.1 Press release of Knowles Corporation dated October 23, 2025.

99.2

Presentation slides dated October 23, 2025.

104Cover Page Interactive Data File (embedded within the Inline XBRL docu