Exhibit 23 - Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the registration statements (Nos. 333-04367, 333-42506, 333-04365, 333-122282, 333-04369, 333-122283, 333-179138, 333-201706, 333-220893, 333-251572, 333-258170, 333-258017, and 333-258019) on Form S-8, and registration statement (No. 333-256401) of Form S-4 of our report dated July 26, 2022, with respect to the consolidated financial statements and financial statement schedule II – Valuation and Qualifying Accounts of MillerKnoll, Inc. and the effectiveness of internal control over financial reporting.

Our report dated July 26, 2022, on the consolidated financial statements, refers to a change in the method of accounting for the cost of certain inventories from the last-in, first-out (LIFO) method to the first-in, first-out (FIFO) method as of June 1, 2019.

/s/ KPMG LLP

Chicago, Illinois

July 26, 2022