What First-Line Supervisors of Office and Administrative Support Workers earn in Contra Costa County, CA
According to the latest federal wage data for the San Francisco-Oakland-Fremont, CA metropolitan area, the median pay for First-Line Supervisors of Office and Administrative Support Workers in Contra Costa County, CA is $88,560 a year, or $42.58 an hour. After federal income tax, Social Security, Medicare and state income tax, the paycheck shrinks to $66,739 a year, and rent, food and energy take another bite. The sections below walk through each step with the actual math for Contra Costa County, CA.
The mean wage is $93,080, which is 5.1% above the median, a sign that a group of high earners lifts the average. The survey counts about 19,480 people working in this occupation across the San Francisco-Oakland-Fremont, CA metropolitan area, so the estimate rests on a substantial pool of workers. Contra Costa County, CA has roughly 1,165,012 residents, according to the population figures used by the rent data.
The salary range, from entry level to top earners
Pay for First-Line Supervisors of Office and Administrative Support Workers in the San Francisco-Oakland-Fremont, CA metropolitan area is not one number. The lowest-paid tenth of workers earn up to $59,980 a year ($28.84 an hour), while the highest-paid tenth earn $131,810 or more ($63.37 an hour). That is a gap of $71,830 between the bottom and the top of the scale. The middle half of workers falls between $72,420 at the 25th percentile and $107,450 at the 75th percentile. A top-tier earner makes 2.2 times what someone at the bottom makes, so experience, certification and employer all matter.
What the hourly rate looks like
Employers quote this occupation by the hour or by the year, so here are both: $42.58 an hour or $88,560 a year at the median for Contra Costa County, CA. Before any deductions, that is $7,380 a month, $3,406 every two weeks and $1,703 each week. After taxes the same job pays $32.09 per hour of take-home income, which is the number that actually has to cover rent and groceries.
How pay in Contra Costa County, CA compares
Compared with the California average
A worker in this occupation in Contra Costa County, CA earns $9,848 more than the California average of $78,712, a premium of 12.5%. Over a year that premium is worth $9,848 before tax and roughly $7,422 after tax. Within California, Contra Costa County, CA already has the highest median we track for this job.
Compared with the national average
The national employment-weighted average for First-Line Supervisors of Office and Administrative Support Workers is $69,509 across the contiguous United States. At $88,560, Contra Costa County, CA pays $19,051 more, which is 27.4% above that benchmark. Keep in mind that a higher salary only helps if living costs do not rise faster, which is why the cost sections below matter as much as the headline number.
Where this job ranks in Contra Costa County, CA
Among the 601 occupations with published wages in Contra Costa County, CA, First-Line Supervisors of Office and Administrative Support Workers ranks number 272 by median pay, ahead of about 55% of them. The best-paying occupation we track here is Computer and Information Systems Managers at $232,890 a year, which is $144,330 more than the median for First-Line Supervisors of Office and Administrative Support Workers.
From gross pay to take-home pay
Three separate tax bills sit between the gross salary and the bank account: federal income tax, FICA, and state income tax. For First-Line Supervisors of Office and Administrative Support Workers earning the Contra Costa County, CA median of $88,560, they add up to $21,821. The result is $66,739 of take-home pay a year ($5,562 a month), based on a single filer using the standard deduction.
Put another way, of every $100 earned, about $25 goes to taxes and $75 reaches the paycheck. The overall effective tax rate is 24.6%.
Federal income tax
After the $15,750 standard deduction, taxable income is $72,810. Federal brackets are marginal, so only the slice of income above each threshold is taxed at the higher rate; the last dollars of this salary fall in the 22% bracket. The resulting federal income tax is $10,932, an effective 12.3% of gross pay, well below the 22% marginal rate because the lower brackets are cheaper.
Social Security and Medicare (FICA)
Payroll taxes are a flat percentage of wages. Social Security takes 6.2% up to a wage base of $176,100, which costs $5,491 on this salary. Medicare takes 1.45%, or $1,284. FICA totals $6,775, which is 7.6% of gross pay.
State income tax in California
California income tax on this salary is $4,114 a year, or 4.6% of gross pay, after the state's own deductions and exemptions are applied. That is 38% of the federal income tax bill, and it comes out to $343 a month. Local taxes such as county or city income taxes are not included, so a few jurisdictions may withhold slightly more.
A cross-check with IRS data for Contra Costa County, CA
IRS Statistics of Income data for Contra Costa County, CA show an average adjusted gross income of $144,130 per return and an average effective federal income tax rate of 17.5% across all filers. Filers in the $75,000 to under $100,000 bracket, where this salary falls, paid an average of 9.5%, compared with the 12.3% estimated here for a single filer taking the standard deduction. Gaps between the two reflect filing status, dependents, credits and other income, none of which a single-person wage estimate includes.
Cost of living in Contra Costa County, CA
Take-home pay only means something next to what life costs. We price four basics for one adult in Contra Costa County, CA: a one-bedroom apartment, food, home energy and gasoline. All of them are converted to annual figures first, then compared with the $66,739 of take-home pay.
Rent
Housing is the largest line in most budgets. For Contra Costa County, CA, HUD sets the Fair Market Rent for a one-bedroom unit at $2,290 a month ($27,480 a year), and at $2,805 for two bedrooms. For First-Line Supervisors of Office and Administrative Support Workers, a one-bedroom absorbs 41.2% of take-home pay and 31.0% of gross pay.
Food
The USDA Thrifty Food Plan (August 2026) puts the cost of a nutritious home-cooked diet for an adult at about $3,436 a year, which is $286 a month or $66.07 a week. That equals 3.9% of gross pay for First-Line Supervisors of Office and Administrative Support Workers in Contra Costa County, CA. It is a thrifty budget with no restaurant meals, so treat it as a floor.
Energy and gasoline
Using California residential prices from the Energy Information Administration and national household averages for consumption, electricity costs about $3,378 a year and other home energy such as natural gas about $751, for $4,129 in total. Gasoline in California averages $4.42 per gallon; at about 463 gallons a year (11,106 miles at 24 miles per gallon) fuel adds $2,047.
What is left over
Rent, food, energy and gasoline cost $37,091 a year in Contra Costa County, CA. Subtract that from $66,739 of take-home pay and $29,647 remains, which is $2,471 a month of breathing room. That margin equals 33.5% of gross pay, a comfortable cushion by common budgeting rules.
Can First-Line Supervisors of Office and Administrative Support Workers afford to live in Contra Costa County, CA?
The 30% rent guideline
A common rule of thumb says rent should stay under 30% of gross income. For a gross salary of $88,560 that ceiling is $2,214 a month. The one-bedroom Fair Market Rent of $2,290 is $76 over it, so rent breaks the guideline. Put as a wage, covering a one-bedroom at the 30% guideline takes $44.04 an hour; the median for First-Line Supervisors of Office and Administrative Support Workers is $42.58, which is 3% below that mark. Another way to see it: at $32.09 of take-home pay an hour, a one-bedroom takes about 16.5 working hours every week.
Splitting a two-bedroom
Sharing a two-bedroom at $2,805 a month means $1,403 each. Compared with renting a one-bedroom alone, that saves $10,650 a year. With a roommate, the yearly margin after the basics becomes $40,297.
How fast you can save
At $2,471 a month of margin, building a $10,000 emergency fund would take about 5 months. Setting aside half of the margin stretches the same goal to about 10 months. These figures ignore interest, raises and any spending beyond the four basics.
Frequently asked questions about First-Line Supervisors of Office and Administrative Support Workers pay in Contra Costa County, CA
How much do First-Line Supervisors of Office and Administrative Support Workers make per hour in Contra Costa County, CA?
The median is $42.58 per hour, based on $88,560 a year over 2,080 hours. Hourly pay runs from about $28.84 at the 10th percentile to $63.37 at the 90th percentile.
How much do First-Line Supervisors of Office and Administrative Support Workers take home after taxes in Contra Costa County, CA?
After federal income tax, FICA and state income tax, the median salary of $88,560 becomes $66,739 a year. That is $5,562 a month, $2,567 every two weeks or $1,283 a week.
How much tax do First-Line Supervisors of Office and Administrative Support Workers pay in Contra Costa County, CA?
Total taxes are $21,821 a year, an effective rate of 24.6%: $10,932 federal income tax, $6,775 FICA and $4,114 California income tax.
Do First-Line Supervisors of Office and Administrative Support Workers earn more in Contra Costa County, CA than elsewhere in California?
Yes. The local median of $88,560 is +12.5% versus the California average of $78,712, a difference of $9,848 a year.
Can First-Line Supervisors of Office and Administrative Support Workers afford a one-bedroom apartment in Contra Costa County, CA?
A one-bedroom costs $2,290 a month against take-home pay of $5,562, which is 41.2% of take-home pay. That does not meet the 30%-of-gross guideline, which allows up to $2,214 a month.
What is the monthly budget margin for First-Line Supervisors of Office and Administrative Support Workers in Contra Costa County, CA?
About $2,471 a month ($29,647 a year) remains after a one-bedroom apartment, food, home energy and gasoline, which together cost $37,091 a year.
What hourly wage covers a one-bedroom in Contra Costa County, CA at the 30% guideline?
$44.04 an hour for a full-time schedule, calculated as the $27,480 annual rent divided by 0.30 and by 2,080 hours. The median for First-Line Supervisors of Office and Administrative Support Workers is $42.58.
How we calculated these numbers
Wages are May 2025 medians from the Bureau of Labor Statistics Occupational Employment and Wage Statistics survey for the San Francisco-Oakland-Fremont, CA metropolitan area; hourly-only values are annualized at 2,080 hours. Rents are HUD Fair Market Rents, food costs come from the USDA Thrifty Food Plan, and energy prices come from the Energy Information Administration. County-level tax statistics come from the IRS Statistics of Income.
Taxes use tax-year 2025 federal brackets, FICA rates and the California rules for a single filer with wage income only. Figures are estimates for planning and comparison, not tax or financial advice, and they exclude local income taxes, benefits, retirement contributions and individual circumstances.