Exhibit 16.1 [GRANT THORNTON LLP LETTERHEAD] October 23, 2003 Securities and Exchange Commission Washington, D.C. 20549 Re: The First of Long Island Corporation File No. 0-12220 Dear Sir or Madam: We have read Item 4(a) of the Form 8-K of The First of Long Island Corporation dated October 24, 2003 and agree with the statements concerning our Firm contained therein. Very truly yours, /s/Grant Thornton LLP