9-1-1

9-1-1 is an emergency telephone number for the North American Numbering Plan (NANP), one of eight N11 codes. Like other emergency numbers around the world, this number is intended for use in life-threatening emergency circumstances only, and to use it for any other purpose (such as making false or prank calls) can be a crime.

In over 98% of locations in the United States and Canada, dialing "9-1-1" from any telephone will link the caller to an emergency dispatch office—called a Public-Safety Answering Point (PSAP) by the telecom industry—which can send emergency responders to the caller's location in an emergency. In approximately 96 percent of the U.S., the Enhanced 9-1-1 system automatically pairs caller numbers with a physical address.

In the United Mexican States, 9-1-1 emergency hotline is available since December 1st. 2016 in the states of Baja California, Colima, Chiapas, Chihuahua, Durango, Guanajuato, Morelos, Nuevo León, Quintana Roo, Sonora, Tlaxcala, Puebla, Zacatecas, Coahuila, Nayarit y Oaxaca. & Since January 3rd 2017, it became available in the states of Baja California Sur, Mexico City DF, Campeche, Querétaro, San Luis Potosí, Tabasco, Aguascalientes, Hidalgo, Jalisco, State of México, Sinaloa, Tamaulipas, Veracruz, Yucatán, Guerrero y Michoacán.

In the Philippines, the 9-1-1 emergency hotline has been available to the public since August 1, 2016, although it was first available in Davao City. It is the first of its kind in Asia-Pacific region. It replaces the previous emergency number 117 used outside Davao City.

999 is used in the United Kingdom and many British territories. 112 is the equivalent emergency number used in the European Union and various other countries. In the US, some carriers, including AT&T, map the number 112 to the emergency number 9-1-1.

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