Mariner's Island Neighborhood, San Mateo
Last updated: October 25, 2026
Crime Rate & Statistics
Above-average safety — lower crime than most neighborhoods
Summary: Mariner's Island, San Mateo Crime Rate (2026)
Mariner's Island, San Mateo, CA has a crime safety grade of B+ as of 2026. The overall crime rate is 17% above the national average.
Data source: FBI UCR & local law enforcement data. Last updated: October 25, 2026.
Safety at a Glance
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in San Mateo
Is Mariner's Island Safe?
Mixed — the grade is relative to other neighborhoods, but crime is above the national average. Mariner's Island in San Mateo, CA has a safety grade of B+. The overall crime index is 117, which is 17% above the national average of 100.
Compared to the San Mateo average (crime index 66), Mariner's Island is 51% higher in overall crime. Residents and visitors should exercise extra caution in this area, particularly after dark.
Looking at specific crime types, murder is the most elevated concern (index: 115, 15% above average), while rape is the lowest risk (index: 10).
Mariner's Island Crime Breakdown
Crime indices compared to national average (100) and San Mateo city average. Higher values mean more crime.
| Crime Type | Index | vs National | Risk Level | |
|---|---|---|---|---|
| Violent Crime | ||||
|
Murder
|
115 | +15% | Moderate | |
|
Assault
|
113 | +13% | Moderate | |
|
Robbery
|
35 | -65% | Low | |
|
Rape
|
10 | -90% | Low | |
| Property Crime | ||||
|
Burglary
|
65 | -35% | Low | |
|
Larceny / Theft
|
98 | -2% | Average | |
|
Vehicle Theft
|
62 | -38% | Low | |
How Mariner's Island Compares
Crime index by category: Mariner's Island vs San Mateo average vs national average.
Crime by Category
Overall Crime Comparison
Mariner's Island Crime Map
Crime heatmap based on block-group level data. Red areas indicate higher crime density.
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Mariner's Island Demographics & Context
Education
Housing
Racial Demographics
Nearby Neighborhoods
Frequently Asked Questions
What is the crime rate in Mariner's Island, San Mateo?
Mariner's Island in San Mateo, CA has a crime safety grade of B+ as of 2026. The overall crime index is 117, which is 17% above the national average. Compared to the San Mateo average, crime in Mariner's Island is 51% higher.
Is Mariner's Island a safe neighborhood in San Mateo?
Mariner's Island has a mixed safety picture with a crime grade of B+, and an overall crime index 117 (17% above the national average). Residents should take standard precautions. The highest concern is Murder (index: 115), while Rape is the lowest risk (index: 10).
How does Mariner's Island compare to the rest of San Mateo?
Mariner's Island's overall crime index is 117, compared to the San Mateo average of 66. This means crime in Mariner's Island is 51% higher than the city average. For violent crime, the index is 68, and for property crime it is 75. However, crime can vary block by block, so checking the crime map for specific streets is recommended.
What type of crime is most common in Mariner's Island?
The most common crime type in Mariner's Island is Assault, with a crime index of 113 (13% above the national average). Homicide is the most elevated type versus the national average (index 115), not the most frequent crime. Overall, property crime is more common than violent crime in this neighborhood, which is consistent with national trends.
What are safer neighborhoods near Mariner's Island?
Nearby neighborhoods with good safety ratings include Mariner's Isle, Parkside, South Shoreview and Lakeshore. These areas are close to Mariner's Island and offer lower crime rates, making them worth considering for residents who prioritize safety.
What are the demographics of Mariner's Island?
Mariner's Island has a population of approximately 388. The median household income is $154,910. The median home value is $1,340,067. Research shows that economic factors can correlate with crime rates, though many other variables play a role in neighborhood safety.
How does Mariner's Island crime compare to the national average?
Mariner's Island's overall crime rate is 17% above the national average (index 117 vs 100). For the most accurate picture, review the per-crime-type breakdown above, as some categories may differ significantly from the overall trend.
Crime data sourced from FBI UCR reports and local law enforcement agencies. Crime indices use 100 as the national average. Updated October 2026.