Sober Truth on Preventing Underage Drinking Reauthorization Act or STOP Act - Amends the Public Health Service Act to reauthorize the program to reduce underage drinking for FY2014-FY2018.

Revises reporting requirements for state programs on underage drinking.

Specifies additional requirements for the development of the national media campaign to prevent underage drinking.

Directs the Administrator of the Substance Abuse and Mental Health Services Administration to make grants to professional pediatric provider organizations to increase effective practices, including the screening of children and adolescents for alcohol use, to reduce the prevalence of alcohol use among individuals under the age of 21, including college students.

Directs the Secretary of Health and Human Services (HHS) to collect data and conduct or support new research on underage drinking that improves and conducts public health surveillance of alcohol use and alcohol-related conditions in states among individuals between age 18 and 20 by increasing the use of surveys, such as the Behavioral Risk Factor Surveillance System, to monitor binge and excessive drinking and related harms.