What does WatchPennies calculate?

WatchPennies estimates cost of living by US county across housing, food, transportation, healthcare, childcare, other necessities, taxes, and income context.

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Contra Costa County, CA vs San Francisco County, CA: Cost of Living Difference

Is it cheaper?

San Francisco County, CA is cheaper than Contra Costa County, CA.

Moving to San Francisco County, CA is estimated to save $1,598 per year.

Cheaper County

San Francisco County, CASave about $1,598 per year.

Salary needed

$50,000 in Contra Costa County, CA is about $48,945 in San Francisco County, CA.

Biggest drivers

Housing increases by $2,133 per year. Transport saves $5,085 per year.

Housing: $2,133 higher in San Francisco County, CA

Taxes: $624 lower in San Francisco County, CA

Childcare: about the same in both counties

Healthcare: $318 higher in San Francisco County, CA

Food: $762 higher in San Francisco County, CA

Transport: $5,085 lower in San Francisco County, CA

Contra Costa County, CA→San Francisco County, CA

Equivalent salary in San Francisco County, CA

$48,945

-2.11% lower

Current salary: $50,000

Household: 1 adult · 0 children

Median Income in Contra Costa County, CA: $146,002

Median Income in San Francisco County, CA: $165,603

Living Index in Contra Costa County, CA 51.94%

Living Index in San Francisco County, CA 44.82%

This estimate matches your purchasing power (equivalent salary) when moving from Contra Costa County, CA to San Francisco County, CA.

* Living index is estimated as (estimated total cost / area median income) * 100. A living index above 100% means modeled costs exceed median income.

Cost of Living Breakdown by Category

Summary

Moving from Contra Costa County, CA to San Francisco County, CA is estimated to save $1,598 per year. A $50,000 salary in Contra Costa County, CA would have similar purchasing power to about $48,945 in San Francisco County, CA. The largest savings come from transport and taxes.

This is a 2.11% decrease in modeled annual costs. Transport is $5,085 per year lower (36.9%); Taxes is $624 per year lower (3.44%).

Below we break down the annual categories behind the difference using Economic Policy Institute 2026 Family Budget data.

What changed the most?

The following cards show the annual category differences that most affect the move to San Francisco County, CA.

Biggest Cost

Largest annual cost increase when moving to San Francisco County, CA

Annual Increase:

$2,133 per year

HOUSING has the largest annual increase when moving to San Francisco County, CA.

Biggest Savings

Largest annual savings when moving to San Francisco County, CA

Annual Savings:

$5,085 per year

TRANSPORT has the largest annual savings when moving to San Francisco County, CA.

Breakdown of price percentages per category.

Numbers are average costs per section.

Category	Difference
Housing	9.17% higher
Contra Costa County, CA San Francisco County, CA Average Cost $23270.00 $25403.00 INFO: Housing costs are based on Department of Housing and Urban Development data. The estimate uses 40th percentile rent for privately owned rental units in each area. Studio apartments are paired with one-adult households, one-bedroom apartments with two-adult households, and two-bedroom apartments with households that have children.
Food	15.32% higher
Contra Costa County, CA San Francisco County, CA Average Cost $4973.00 $5735.00 INFO: Food costs are based on the U.S. Department of Agriculture's food plans. Numbers are normalized to each area using Feeding America and Meal Gap data. This estimate assumes most food is bought at local grocery stores and prepared at home.
Transport	-36.90% lower
Contra Costa County, CA San Francisco County, CA Average Cost $13780.00 $8695.00 INFO: Transportation costs are a combination of auto ownership, auto use, and public transit. Data is collected from the Center for Neighborhood Technology (CNT).
Healthcare	4.60% higher
Contra Costa County, CA San Francisco County, CA Average Cost $6920.00 $7238.00 INFO: Healthcare expenses come from average insurance premiums and out-of-pocket costs. The estimate assumes families purchase the lowest-cost available insurance plan under the Affordable Care Act. Data comes from Kaiser Family Foundation and the U.S. Department of Health and Human Services (HHS).
Other Costs	10.24% higher
Contra Costa County, CA San Francisco County, CA Average Cost $8769.00 $9667.00 INFO: This cost is calculated through the average spending of categories deemed necessary by the Bureau of Labor Statistics Consumer Expenditure Survey. These include apparel, personal care, household supplies, reading materials, and school supplies.
Childcare	0.00% higher
Contra Costa County, CA San Francisco County, CA Average Cost $0.00 $0.00 INFO: Childcare expenses are based on combined costs for center-based care and family-based care for 4-year-olds and school-aged children. For households with one child, the estimate assumes the child is 4 years old. For households with two children, the estimate assumes the second child is 8 years old.
Taxes	-3.44% lower
Contra Costa County, CA San Francisco County, CA Average Cost $18115.00 $17491.00 INFO: Taxes are calculated from the National Bureau of Economic Research. The number weighs in personal income tax, state income tax, federal Social Security, and Medicare taxes.

In San Francisco County, CA, modeled annual costs are $74,229 compared with $75,827 in Contra Costa County, CA.

Overall, annual costs are lower in San Francisco County, CA. The category breakdown above shows where the move creates the most room in the budget.

In this case San Francisco County, CA and Contra Costa County, CA are both metropolitan locations.

Use our map to visually compare multiple counties at once.

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