EXHIBIT 23.1 CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM We consent to the incorporation by reference in Registration Statement No. 333-122934 on Form S-8 of our report dated March 2, 2006 (which report expresses an unqualified opinion and includes explanatory paragraphs relating to the adoption of Statements of Financial Accounting Standards Nos. 123(R) in 2005 and 123 in 2003 and related party transactions), relating to the financial statements of Wright Express Corporation, appearing in this Annual Report on Form 10-K of Wright Express Corporation for the year ended December 31, 2005. /s/ DELOITTE & TOUCHE LLP Boston, Massachusetts March 15, 2006