Before you commit to a payment, pull the parcel's assessed value, multiply it by the county's FY2026 rate of $0.906 per $100, and divide by 12. That monthly tax figure belongs next to principal, interest, insurance, and any association dues, because the full total is what your lender and your lifestyle both have to carry.
Buyer’s Monthly Budget and Prince William Property Taxes
How do property taxes fit into a Buyer’s Monthly Budget in Prince William County?
Prince William County applies its real-estate tax rate to a home's assessed value, not what you paid for it. The FY2026 rate is $0.906 per $100 of assessed value, so dividing the annual tax by 12 gives you the tax line of your Buyer’s Monthly Budget. The county's published FY2026 average residential bill is $5,162, but your actual bill depends on the address and its assessment.
Key Takeaways
- The FY2026 county real-estate tax rate is $0.906 per $100 of assessed value, which the Board of County Supervisors adopted on April 22, 2025, down from $0.920.
- At that rate, every $100,000 of assessed value produces $906 in annual county real-estate tax, or $75.50 per month.
- The county's published FY2026 average residential bill of $5,162 works out to about $430.17 a month, but it is an average and not a quote for any address.
- Real-estate taxes are generally billed in two installments, due July 15 and December 5, so you need to set money aside every month between them.
- Taxes are calculated on the assessed value, so use the parcel's assessment and not your offer price when you build your payment.
How do you calculate Prince William County property taxes for your Buyer’s Monthly Budget?
Multiply the assessed value by 0.906, divide by 100 to get the annual county real-estate tax, then divide by 12 for the monthly figure. It is simple arithmetic, but it only works if you start with the right assessment.
Here is the formula:
- Annual tax = assessed value × (0.906 ÷ 100)
- Monthly planning figure = annual tax ÷ 12
To get a feel for the scale, the table below shows the verified county figures and what they mean when you're budgeting.
| Item | Figure | How to use it |
|---|---|---|
| FY2026 real-estate tax rate | $0.906 per $100 of assessed value | Apply it to the parcel's assessment |
| Every $100,000 of assessed value | $906 per year, or $75.50 per month | Rate arithmetic you can scale to any assessment |
| Published FY2026 average residential bill | $5,162 per year, about $430.17 per month | County-wide average, not a quote for one address |
| First-half installment | Due July 15 | Reserve money in the months before |
| Second-half installment | Due December 5 | Reserve money in the months before |
Does the county tax your purchase price or the assessed value?
The county taxes the assessed value. The county expresses the rate as dollars per $100 of assessed value, and the assessment can be different from what you negotiate with a seller.
That's why I never multiply an offer price by the tax rate and call it done. The reliable move is to look up the parcel's current assessment on the county's real estate tax, appeals, and assessments page and confirm the tax account before you finalize your numbers. Whether you're looking in Gainesville, Haymarket, Bristow, or Manassas, the method is the same, but the result is different for every address.
Why can your tax bill rise even when the rate falls?
Because the bill is the rate multiplied by the assessment, a lower rate can still produce a higher bill if the assessment rises by more. The Board of County Supervisors lowered the rate from $0.920 to $0.906 for FY2026 specifically to offset rising assessments, which tells you the two numbers move together.
For regional context, the Northern Virginia Association of Realtors® reported a September 2026 regional median sold price of $744,950, up 4.2% from September 2025. The same association's September report showed 1,250 closed sales, 3,477 active listings, 28 average days on market, and 2.5 months of supply. That report covers Fairfax and Arlington counties and several nearby cities and towns, not Prince William County, so treat it as a regional backdrop and not as a Prince William tax or price number.
What it does show is that values across the region have been moving, and that's the reason to check the assessment on any home you're seriously considering. The rate will not tell you the whole story.
What does the $5,162 county average actually tell you?
It tells you roughly where the middle of the county sits, and nothing about your target home. The county's FY2026 budget materials publish that figure as an average residential bill, and spread over 12 months it is about $430.17.
A home with a higher assessment will land above it and a lower assessment will land below it. Your exact number depends on the property's location, assessment, classification, any exemptions or adjustments, and any non-county charges tied to the parcel. This is where a parcel-level review earns its keep, and it's something I do with my buyers before they write an offer.
When are Prince William County property taxes due, and can you pay monthly?
Real-estate taxes are generally billed in two installments, with the first half due July 15 and the second half due December 5, according to the county's Finance department. The county also publishes a monthly-installment option, so confirm what applies to your account.
Two large bills a year are easy to forget when you're comparing monthly payments. If you only budget for the mortgage, a due date can arrive without a cushion behind it. The cleaner approach is to treat one-twelfth of the annual tax as a fixed monthly cost and set it aside, whether or not your lender collects it with your payment. Ask your lender how taxes and insurance will be handled on your loan.
How does the monthly-installment option work?
Under the county's published schedule, the first installment is due July 15, later installments are due on the fifth of the month, and the final payment is due June 5. The county's monthly installments page is the place to confirm eligibility, enrollment, and any account-specific requirements before you rely on that schedule. I'd get that answer in writing from the county for your specific account, not assume it carries over automatically when you buy.
What else belongs in your monthly housing budget besides taxes?
Beyond principal and interest, a complete payment includes real-estate taxes, homeowners insurance, mortgage insurance if your loan requires it, and any homeowners' or condominium association dues. Only the tax line can be built from the county's assessment and rate; the others come from your lender, an insurance quote, and the community's own documents.
- Principal and interest: comes from your loan terms and rate, so get a current quote from your lender.
- Real-estate taxes: assessed value × 0.906 ÷ 100 ÷ 12, verified against the parcel's actual account.
- Homeowners insurance: request a quote on the specific property, not a general estimate.
- Mortgage insurance: applies only if your loan type or down payment calls for it, so confirm with your lender.
- Association dues: vary by community and by what the dues cover, so read the governing documents before you commit.
I've seen buyers focus on principal and interest and then feel pinched once the rest of the payment shows up. Two homes with the same list price can carry noticeably different monthly totals once you run all five lines. If you're newer to the process, my Prince William County first-time home buyer steps show where this budgeting fits. Costs at the closing table are a separate matter from these recurring ones, and I cover them in my post on grantor's tax and congestion relief fees in Prince William.
Your numbers depend on the address, the assessment, your loan, and your insurance, and that's the work I do with every buyer before we write an offer.
FAQ
How much are property taxes in Prince William County, Virginia?
It depends on the property's assessed value, because the county applies its rate to that assessment. The FY2026 rate is $0.906 per $100 of assessed value, and the county's published FY2026 average residential bill is $5,162. Your own bill will differ based on your address and assessment.
Does Prince William County tax my home's purchase price or its assessed value?
The county taxes the assessed value. The purchase price can be different from the assessment, so look up the parcel's county assessment and confirm the tax account instead of multiplying your offer price by the rate.
When are Prince William County property taxes due, and can I pay monthly?
Real-estate taxes are generally due in two installments, July 15 and December 5. The county also publishes a monthly-installment option, with the first payment due July 15, later payments on the fifth of the month, and the final payment due June 5. Confirm eligibility and enrollment with the county before relying on it.
Why can my property-tax bill rise even if the tax rate falls?
Your bill is the rate multiplied by your assessed value, so a rising assessment can outweigh a lower rate. The county lowered its rate from $0.920 to $0.906 for FY2026 to offset rising assessments, but individual bills still depend on each parcel's assessment.
What should I include in my monthly housing budget besides mortgage principal and interest?
Include real-estate taxes, homeowners insurance, mortgage insurance if your loan requires it, and any homeowners' or condominium association dues. Of those, only the tax line can be calculated from the county assessment and rate; get the rest from your lender, an insurance quote, and the community's documents.
Ready to see your real monthly number?
The county rate is the easy part. Your Buyer’s Monthly Budget is only accurate once it uses the real assessment, a real insurance quote, and your lender's loan terms for the specific home you're considering. If you'd like me to walk through that with you for properties you're looking at, get a free home valuation and book a consultation with me, and we'll build your numbers together before you make an offer.
Equal Housing Opportunity. Real estate licensees in Virginia are regulated by the Virginia Real Estate Board. This article is general information, not legal, tax, or financial advice; confirm your own numbers with your title company, tax advisor, or lender, and verify your property's assessment and tax account with Prince William County.