Sun Valley, Texas
Sun Valley is a small community in Lamar County in far northeastern Texas, lying about 79 miles northeast of McKinney. It sits amid the gently rolling farmland and pasture of the Blackland and post-oak country of the region. The area is rural in character, with agriculture and open land dominating the landscape around it.
Place essentials
Official Census snapshot- Census place type
- City
- July 2025 population
- 77
- Change from 2020 base
- +8.5%
- Land area
- 0.2 sq. mi.
- County footprint
- Lamar County
Place type, county footprint, and land area use the Census Bureau's January 1, 2025 geography. Population uses Vintage 2025 estimates through July 1, 2025; change compares that estimate with the April 1, 2020 estimates base. Geography file | Population file
Property here runs through the appraisal district and tax office for Lamar County. The homestead exemption, appraisal cap, protests, and any MUD, PID, or special districts all sit at the parcel level.
Official routes
Use the office for the parcel address; a mailing city is not always the governing city.
County context
What to know around Sun Valley
County lines carry much of the property, land, water, and outdoors context around Sun Valley.
County Origins
Lamar County Was Founded in 1840 and Named for a Republic President
Lamar County was created by the Republic of Texas in 1840 and named for Mirabeau B. Lamar, the fourth president of the Republic.
Property Tax Basics
Who Appraises and Who Collects Your Property Taxes
Two separate offices handle your property taxes in Lamar County: one sets the value, the other handles payment.
Local History
Paris Burned Twice and Rebuilt Both Times
Major fires in 1877 and 1916 destroyed much of Paris, which is why most of the older downtown buildings date from the early 20th century.
Nearby
Places near Sun Valley
Nearby counties
Local notes for nearby counties
Next steps for Sun Valley
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