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 District of Columbia, DC: Cost of Living Difference

Is it cheaper?

District of Columbia, DC is cheaper than Contra Costa County, CA.

Moving to District of Columbia, DC is estimated to save $4,974 per year.

Cheaper County

District of Columbia, DCSave about $4,974 per year.

Salary needed

$50,000 in Contra Costa County, CA is about $46,720 in District of Columbia, DC.

Biggest drivers

Food increases by $462 per year. Transport saves $3,678 per year.

Housing: $275 lower in District of Columbia, DC

Taxes: $1,519 lower in District of Columbia, DC

Childcare: about the same in both counties

Healthcare: $21 lower in District of Columbia, DC

Food: $462 higher in District of Columbia, DC

Transport: $3,678 lower in District of Columbia, DC

Contra Costa County, CA→District of Columbia, DC

Equivalent salary in District of Columbia, DC

$46,720

-6.56% lower

Current salary: $50,000

Household: 1 adult · 0 children

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

Median Income in District of Columbia, DC: $150,381

Living Index in Contra Costa County, CA 51.94%

Living Index in District of Columbia, DC 47.12%

This estimate matches your purchasing power (equivalent salary) when moving from Contra Costa County, CA to District of Columbia, DC.

* 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 District of Columbia, DC is estimated to save $4,974 per year. A $50,000 salary in Contra Costa County, CA would have similar purchasing power to about $46,720 in District of Columbia, DC. The largest savings come from transport and taxes.

This is a 6.56% decrease in modeled annual costs. Transport is $3,678 per year lower (26.69%); Taxes is $1,519 per year lower (8.39%).

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 District of Columbia, DC.

Biggest Cost

Largest annual cost increase when moving to District of Columbia, DC

Annual Increase:

$462 per year

FOOD has the largest annual increase when moving to District of Columbia, DC.

Biggest Savings

Largest annual savings when moving to District of Columbia, DC

Annual Savings:

$3,678 per year

TRANSPORT has the largest annual savings when moving to District of Columbia, DC.

Breakdown of price percentages per category.

Numbers are average costs per section.

Category	Difference
Housing	-1.18% lower
Contra Costa County, CA District of Columbia, DC Average Cost $23270.00 $22995.00 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	9.29% higher
Contra Costa County, CA District of Columbia, DC Average Cost $4973.00 $5435.00 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	-26.69% lower
Contra Costa County, CA District of Columbia, DC Average Cost $13780.00 $10102.00 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	-0.30% lower
Contra Costa County, CA District of Columbia, DC Average Cost $6920.00 $6899.00 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	0.66% higher
Contra Costa County, CA District of Columbia, DC Average Cost $8769.00 $8827.00 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 District of Columbia, DC 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	-8.39% lower
Contra Costa County, CA District of Columbia, DC Average Cost $18115.00 $16596.00 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 District of Columbia, DC, modeled annual costs are $70,853 compared with $75,827 in Contra Costa County, CA.

Overall, annual costs are lower in District of Columbia, DC. The category breakdown above shows where the move creates the most room in the budget.

In this case District of Columbia, DC and Contra Costa County, CA are both metropolitan locations.

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