112th Congress (2nd) Vote 89 - A bill to amend the Higher Education Act of 1965 to extend the reduced interest rate for Federal Direct Stafford Loans, and for other purposes.

Stop the Student Loan Interest Rate Hike Act of 2012 - Amends title IV (Student Assistance) of the Higher Education Act of 1965 to make the 3.4% interest rate on Direct Stafford loans first disbursed to undergraduate students between July 1, 2011, and July 1, 2012, applicable to Direct Stafford loans first disbursed to undergraduate students between July 1, 2011, and July 1, 2013.

Amends the Internal Revenue Code and title II (Old Age, Survivors and Disability Insurance) of the Social Security Act to require certain shareholders of a subchapter S corporation engaged as a partner in a professional service business to include income or loss attributable to such business in their net earnings from self-employment for employment tax purposes.

Restricts such tax treatment to shareholders whose modified adjusted gross income exceeds a specified amount that varies based on their tax filing status.

Defines a "professional service business" as any trade or business providing services in the fields of health, law, lobbying, engineering, architecture, accounting, actuarial science, performing arts, consulting, athletics, investment advice or management, or brokerage services.