Population of Ontario, California as of April 2025. How many people live in Ontario today?

The exact population of Ontario, California as of April 2025 is estimated at 175,265 residents. Please note: this figure is an estimate and may slightly change as people get born and pass away, it also depends on migration to/from Ontario.

Check out more data on population in California:

• Population of Modesto
• Population of Oxnard
• Population of San Diego
• Population of Long Beach
• Population of Huntington Beach
• Population of Garden Grove
• Population of Lancaster
• Population of Pomona
• Population of Torrance
• Population of Fullerton
• Population of Concord
• Population of Berkeley
• Population of Ventura
• Population of Richmond
• Population of Santa Maria
• Population of El Cajon
• Population of Rialto