South Monrovia Island, CA population, income and ZIP codes

South Monrovia Island CDP is a mid-size town in California, with 7,072 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #576 of 1,618 ranked by population — larger than 64% of them. The median age here is 34.4 years against 39.1 nationally, a slightly younger profile than the country as a whole. Places under 65,000 residents only appear in the five-year release, never the one-year file, so these values pool sixty months of responses and lag the current year by design.

Households in South Monrovia Island CDP earn a median of $109,730 a year, 39.7% above the national figure of $78,538 and 20% above the $91,111 median for the 1,050 California cities we cover. The median is the midpoint household, not an average, so a handful of very high earners cannot drag it upward the way they distort a mean. Poverty reaches 6% of residents here, less than half the 12.4% national rate.

The typical owner-occupied home in South Monrovia Island CDP is valued at $660,800, 117.8% above the national figure and 12% above the $589,600 peer median, while median gross rent runs $1,985 a month, 41.2% above the national figure, or roughly $23,820 across a full year. A household on the local median income would put about 21.7% of gross pay toward that rent against the federal 30% cost-burden threshold, so renting here is within the standard affordability guideline. The home-price-to-income ratio works out to 6×, against roughly 3.9× nationally, so buying is harder here than in the average US market. 66.7% of occupied homes are owner-occupied versus 65% nationally, so the market leans toward owners. The rent line includes utilities paid by the tenant, a definition worth remembering when comparing it against a landlord's quoted rate.

Every value on this page is published directly by the Census for this area — nothing is modelled or interpolated. Small-area estimates still carry wider margins of error than state or national figures, so check the linked ACS tables before relying on them for lending, appraisal or legal work.