Your rate went down and your bill went up. Here is how that happens.

Every spring, a county board announces a real estate tax rate, and every spring, residents compare it to last year's and draw the wrong conclusion. In 2026 Fairfax County lowered its rate to $1.12, and the average homeowner's bill went up $337. Falls Church lowered its rate too, and the median homeowner will pay $557 more. Arlington raised its rate 2 cents, and the average bill went up $466. Prince William cut its rate from $0.906 to $0.865, and the average bill went down $56.

None of that is a contradiction. It is arithmetic, and the arithmetic is worth understanding, because it explains why the makeup of the tax base matters more than the rate.

Your bill is assessment times rate

A real estate bill is your home's assessed value, divided by 100, times the rate. If your assessment rises 8% and the rate falls 2%, your bill goes up. In most of Northern Virginia, residential assessments have risen every year since the pandemic, because home prices have. So a small rate cut is a smaller cut than it looks, and a flat rate is a tax increase.

The levy comes first

A locality does not start with a rate. It starts with a budget: what it needs to spend on schools, public safety, roads, parks and debt. Then it looks at the total assessed value of everything on its land books and sets the rate that will raise the budget. The rate is the output, not the input.

Virginia law recognizes this. When a reassessment raises a locality's total value by more than 1%, Va. Code § 58.1-3321 requires it to calculate and publish the "lowered rate" that would produce the same revenue as the year before, and to hold a separate public hearing if it wants to adopt anything higher. Any rate above that lowered rate is, by law, an effective tax increase, even if it is below last year's number.

Who pays depends on who else is on the books

Here is the part that connects the rate to the tax base. If the total levy is fixed by the budget, then the share paid by homeowners is whatever is left after businesses pay theirs. When commercial values fall, as Arlington's office values did by 19% in a year and Fairfax's commercial values have for three straight years, the levy does not fall with them. It shifts. Residential assessments carry more of it, which is why bills rise even when the rate is cut.

The reverse is also true. In Prince William, where commercial and industrial property, including data centers, is about 34% of the real estate base, the board was able to cut the rate 4 cents and the average bill actually fell. In Loudoun, where the share is about 37%, the rate is $0.805, the lowest in the region.

What to watch for next spring

• The lowered rate. It is in the budget advertisement. Compare the proposed rate to that, not to last year's rate.
• The average bill. Most counties publish the change in the average residential bill alongside the rate. That is the number that describes what happens to you.
• The commercial share. The assessment report says how much of the base is residential and how much is commercial. If the commercial share is falling, your bill is going up, whatever the rate does.

The way to keep homeowners' bills flat is a broader base, with more businesses sharing the cost of the same schools and services. That is what every one of the numbers above is pointing at.