Ontario to San Marcos, California: Road Trip Guide & Distance

How far is Ontario from San Marcos, California?

The distance from Ontario to San Marcos, California is 69.4 miles (111.7 km) as the crow flies. San Marcos, California is located SSE of Ontario. By car, the driving distance is approximately 86.7 miles, taking about 1h 45min. A direct flight would take roughly 38min. Both are located in United States.

This is a quick and easy drive, perfect for a day trip or weekend getaway. You can easily make the round trip in a single day. Heading East means you'll be driving into the sunrise if you start early. Keep your windshield clean for the best visibility. Given the short distance, driving or taking a train is often faster and more convenient than dealing with airport security and flight boarding times.

Coordinates come from public place data for Ontario and San Marcos, California. The driving distance is estimated from straight-line distance with a road-factor model, so confirm the route in your navigation app. Fuel, flight, bus, and train values are planning estimates and can change by date, provider, road closures, and border rules.