|County||San Diego County|
East County does not have an official geographic definition, although East County boundaries are unofficially drawn by the County of San Diego for its Supervisorial District 2. It commonly includes the four cities east of San Diego—El Cajon, La Mesa, Lemon Grove and Santee—as well as suburban and rural unincorporated communities such as Lakeside, Spring Valley, Jamul, and Alpine. Many sources also include vast swaths of the backcountry of San Diego County also known as the Mountain Empire, including communities along Interstate 8 such as Pine Valley and Descanso, and communities along the rural section of California State Route 94 such as Potrero, Boulevard, and Jacumba. Other sources consider communities within the entire eastern two-thirds of the county to be East County, thereby encompassing places like Ramona, Julian, and Borrego Springs, The Ramona area—Ramona, San Diego Country Estates and —is often considered part of inland North County due to its association with Rancho Bernardo, Escondido and other North County Inland communities.
The populace of East County primarily dwells in the interior valleys east of San Diego proper while some development encroaches on the coastal foothills.
A broader definition of East County exists that includes the Cuyamaca Mountains and the Laguna Mountains, as well as the desert area of Anza-Borrego State Park. Yet, this definition, when used by SANDAG, excludes the East Suburban centers.
Prominent geologic formations include El Capitan, a large dome-shaped mountain overlooking Santee and Lakeside, as well as Iron Mountain and Mount Woodson that overlook Poway.
Populations listed are 2010 Census populations:
- La Presa – 34,169
- Spring Valley – 28,205
- Rancho San Diego – 21,208
- Lakeside – 20,648
- Winter Gardens – 20,631
- Casa de Oro-Mount Helix - 18,762
- Alpine – 14,236
- Jamul – 6,163
- Harbison Canyon – 3,841
- Granite Hills – 3,035
- Crest – 2,593
- Pine Valley – 1,510
- Descanso – 1,423
Primary and secondary schools
East County is served by Santee School District, Grossmont Union High School District, Cajon Valley Union School District, Lakeside Union School District, Lemon Grove School District, Poway Unified School District.
Grossmont College, located in El Cajon, and Cuyamaca College, located in Rancho San Diego, are two community colleges in the East County region. San Diego Christian College is located in Santee. Berean Bible College is located in Poway.
- See, e.g., District 2 Boundaries 
- See, e.g., East County Magazine neighborhoods, . Retrieved 19 March 2011.
- See, e.g., Mellin, Maribeth, and Onstott, Jane. Insider's Guide to San Diego. 5th ed. Morris Book Publishing. 2010. p. 8
- See also Vaughn, Jacqueline, and Cortner, Hanna J. Funding Fire: A Losing Proposition? The California Journal of Politics and Policy. Vol. 2, Issue 1. 2010. p.10.
- North County Times: Coastal and Inland cities
- Mellin, Maribeth, and Onstott, Jane. Insider's Guide to San Diego. 5th ed. Morris Book Publishing. 2010. p. 8
- "MSA: East Suburban". Retrieved April 10, 2011.