Strengthening Loan Forgiveness for Public Servants Act This bill amends title IV (Student Assistance) of the Higher Education Act of 1965 to direct the Department of Education (ED) to cancel 15%, 15%, 20%, 20%, and 30% of the amount a borrower owes after 2, 4, 6, 8, and 10 years of public service employment, respectively, on a William D. Ford Federal Direct Loan made after this bill's enactment. (Currently, the balance of a borrower's Direct Loan is canceled if the borrower is not in default and has made 120 monthly payments on such loan while employed as a public service employee.) The bill: (1) requires borrowers availing themselves of such loan cancellation to submit an employment certification form that includes self-certification of employment and employer certification of employment dates, and (2) places the borrower's loan in deferment during the period in which the borrower is employed in an eligible public service job if the borrower submits such form to ED. If a portion of a loan is canceled for any year, the interest on such loan for such year must be canceled.