Exhibit 5

Sidley Austin LLP 787 Seventh Avenue New York, NY 10019 +1 212 839 5300 +1 212 839 5599     AMERICA · ASIA PACIFIC · EUROPE

October 3, 2022

Caterpillar Financial Services Corporation

2120 West End Avenue

Nashville, Tennessee 37203-0001

Ladies and Gentlemen:

At your request, we have examined the Registration Statement on Form S-3 (the “Registration Statement”), in the form to be filed with the Securities and Exchange Commission (the “Commission”) in connection with the registration under the Securities Act of 1933, as amended (the “Act”), of Variable Denomination Floating Rate Demand Notes (the “Notes”) of Caterpillar Financial Services Corporation, a Delaware corporation (the “Company”). The Notes are to be issued from time to time under an Indenture, dated as of July 15, 1991, as supplemented by a First Supplemental Indenture, dated as of October 1, 2005 (collectively, the “Indenture”), between the Company and U.S. Bank Trust National Association, as successor trustee, copies of which are included as exhibits to the Registration Statement. The Notes are to be sold from time to time as set forth in the Registration Statement, any amendment thereto, the prospectus contained therein (the “Prospectus”) and any supplements to the Prospectus.

We have examined the Registration Statement and such other instruments, documents, and records which we deemed relevant and necessary for the basis of our opinion hereinafter expressed. In such examination, we have assumed the following: (a) the authenticity of original documents and the genuineness of all signatures; (b) the conformity to the originals of all documents submitted to us as copies; and (c) the truth, accuracy, and completeness of the information, representations, and warranties contained in the records, documents, instruments, and certificates we have reviewed.

Based on such examination, we are of the opinion that, when the Registration Statement shall become effective, the Notes, when issued in accordance with the Indenture and the Cat Financial PowerInvestment Plan (filed as an exhibit to the Registration Statement) and in the manner contemplated by the Registration Statement, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their terms.

With respect to enforcement, the above opinion is qualified to the extent that enforcement of the Indenture and the Notes may be limited by applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally, concepts of reasonableness and equitable principles of general applicability (including, without limitation, concepts of good faith, fair dealing and the lack of bad faith), provided that we express no opinion as to the effect of fraudulent conveyance, fraudulent transfer or similar provisions of applicable law on the conclusions expressed above.

The foregoing opinion is given as of the date hereof and is limited to matters arising under the laws of the State of New York and the General Corporation Law of the State of Delaware as in effect on the date hereof. We hereby consent to the filing of this opinion as an exhibit to the above-referenced Registration Statement and to the use of our name wherever it appears in the Registration Statement and any amendment thereto. In giving such consent, we do not thereby admit that we are within the category of persons whose consent is required by Section 7 of the Act or the related rules and regulations of the Commission issued thereunder with respect to any part of the Registration Statement, including this opinion as an exhibit or otherwise.