STALKERS Act of 2013 - Amends the federal criminal code to revise the definition of stalking and impose criminal penalties on anyone who, with intent to kill, physically injure, harass, or intimidate a person or to place a person under surveillance with the intent to kill, physically injure, harass, or intimidate such person, travels in interstate or foreign commerce or within the special maritime and territorial jurisdiction of the United States or enters or leaves Indian country and: (1) causes or attempts to cause bodily injury or serious emotional distress to another person, or (2) engages in conduct that would be reasonably expected to cause serious emotional distress to another person.

Imposes the same criminal penalties on anyone who, with intent to kill, physically injure, harass, or intimidate a person, engages in a course of conduct in or substantially affecting interstate or foreign commerce that: (1) causes or attempts to cause bodily injury or serious emotional distress to another person, or (2) occurs in circumstances where the conduct would be reasonably expected to cause another person serious emotional distress.

Increases penalties for stalking offenses if: (1) the offense involves conduct in violation of a protection order, or (2) the victim of the offense is under the age of 18 or over the age of 65.

Requires the annual report of the Attorney General to include an evaluation of efforts to enforce laws relating to stalking and to identify and describe elements of such efforts that constitute the best practices for the enforcement of such laws.

Provides for compliance of the budgetary effects of this Act with the Statutory Pay-As-You-Go Act of 2010.