Los Altos Hills, CA has a population of 8,376 and is the 4,535th largest city in the United States. The population density is 937 per sq mi which is 303% higher than the California average and 935% higher than the national average. The median age in Los Altos Hills is 51 which is approximately 42% higher than the California average of 36. In Los Altos Hills, 78% of the population over 15 years of age are married, 64% speak English and 4% speak Spanish. 36% of Los Altos Hills residents were born in California, 29% were born out of state, 2% were born outside of the United States and 32% were foreign born.