Exhibit 15.1

Consent of Independent Registered Public Accounting Firm

We hereby consent to the incorporation by reference in the Registration Statement on Form F-3 (No. 333-265891) of Santander UK plc of our report dated 7 March 2023 relating to the financial statements, which appears in this Form 20-F.

/s/ PricewaterhouseCoopers LLP

London, United Kingdom

7 March 2023

Santander UK plc 1