AppealHarbor Jurisdiction Fairfax County, VA Tax year 2026 Reviewed 2026-08-02

Reading your Fairfax County assessment notice

Last reviewed 2026-08-02, against the county's 2026 appeal forms and the current Virginia Code. The 2027 forms and dates have not been published yet.

An envelope from the Department of Tax Administration arrives in February, and inside is a number bigger than last year's. The number is the part that registers.

The notice is telling you more than that, and one line on it matters far more than the others.

This page walks through what the notice says, how the county arrived at the figures, and what your options are if you think it is wrong.

In 30 seconds:

  • The notice shows a land value, a building value, and a total. The total is the number that matters.
  • It is not a bill. It does not set your tax rate, and it is not a demand for payment.
  • The value is the county's estimate of what your property was worth on January 1, produced by valuing large groups of similar properties at once.
  • A large jump in the land portion is not, by itself, something to appeal.
  • Neither is the size of the increase. The county says so on its own form.
  • If you disagree, the clock is short — roughly six weeks from the notice to the first deadline.

If your tax bill comes from the City of Fairfax or the City of Falls Church, those cities assess separately, send their own notices, and set their own deadlines.

What the notice actually shows

Three figures, and they do different jobs.

Land value is the county's estimate for the lot on its own.

Building value — you may see it called improvements — is the estimate for the house and anything else built on the lot.

Total is the two added together, and it is the number your tax is calculated from.

Read the total first. The split between the other two moves around from year to year for reasons that have nothing to do with your house. Chasing that movement leads to an argument the county has already answered, as the next section shows.

Why the land and building split matters less than it looks

Say your land value rose sharply while the building value barely moved, or even fell. That looks wrong. In the county's framing it is not — at least not in a way an appeal can reach.

The county states its position directly. The Board of Equalization is the independent county board that hears assessment appeals, and on its pages the county explains that uniformity of the tax burden is a function of the total assessed value, and that large increases in land value or improvement value are not errors in the assessment so long as the change in the total assessed value is uniform as measured by market value evidence.

So "my land value went up forty percent" is not a case on its own. The question the county will ask is whether the total is defensible.

That is not the same as saying the split never matters. It means the split is not the argument. Why a big increase is not a legal ground covers what the law looks at instead.

How the county arrived at the number

Nobody visited your house to produce that figure.

The county reviews assessed values for all real property each year, with January 1 as the effective date. For most residential property, it determines fair market value (what the property would sell for on the open market) from comparable sales data, analyzing recently sold properties using computer-assisted techniques.

The county's own definitions page is clearer about what that means than most explanations manage. An assessment is a mass valuation, done once a year, that analyzes large numbers of sales to set values for large groups of similar properties. A detailed valuation of one specific property is a different exercise.

Two things follow from that, and both matter if you are thinking about an appeal.

The date is fixed. The value is an estimate of what your property was worth on January 1. What happened to the market in March is next year's question. Assessments are made on the information the county had before that date.

The method works on groups. A process built to value thousands of properties at once cannot look closely at any one of them. That is not a flaw in the county's work — it is what mass valuation is, and it is done that way everywhere. But it is where an appeal gets its opening, because the county's file on your particular house may be wrong, or your house may differ from the group it was valued with.

What the county-wide percentage tells you

Every year the county publishes a percentage, and every year it gets read as though it applied to individual houses. It does not — and the figure is not the thing most coverage says it is.

For 2026, with notices mailed beginning February 17, Fairfax reported a residential equalization change of 3.99%. That is the change to the aggregate residential assessment base — the total roll — not an average of what happened to individual houses. The county says as much in the same release: the percentages represent the aggregate change to the overall tax base, and are not necessarily indicative of a change to any single property.

The figures that do describe properties sit further down the same release. Mean 2026 assessed values: single-family detached $1,012,504, up 4.28%; townhouse $612,580, up 3.90%; condominium $387,560, up 2.94%.

More useful still is the spread. Of 339,576 residential parcels in the equalization group, 275,585 rose, 26,645 fell, and 37,346 did not change. Close to one property in five did not go up at all — which is exactly what a single headline percentage hides.

Your notice can show a rise well above any of these numbers or well below, and neither fact is evidence of anything by itself. The county’s figures describe the roll; your figure describes your parcel.

It is also not a ground. The 2026 administrative appeal form states plainly that financial impact and the rate of value change are not sufficient grounds for appeal — and the county's appeals page says that simply saying the increase in value is too much in a single year is not a legal basis for an appeal.

What the notice is not

It is not a bill. Bills come later, in two installments. The notice tells you the value your bill will be calculated from.

It does not set your tax rate. The Board of Supervisors sets the rate each spring through the budget process. No appeal route can change it, and an appeal is not the way to object to it.

It is not final. It is the county's estimate, and estimates can be contested — but on the grounds the law recognizes, not on the size of the number.

The clock, and it is short

Fairfax mails notices in February. The administrative appeal deadline is April 1. That is about six weeks, and it includes the time you need to gather anything you intend to send.

The Board of Equalization deadline is June 1. It is a separate route with a later deadline, and you do not have to have tried the administrative route first.

Whether a filing counts as on time depends on how you send it. Anything filed online, emailed or uploaded must be received by 4:30 p.m. on the deadline date, and that applies to both routes. Mail is judged by postmark instead, and the two routes word it differently: the administrative appeal must be postmarked by April 1, while the Board of Equalization application must be postmarked by midnight on June 1. Every appeal deadline, and the rules behind them has the detail. One rule worth knowing now: the county extends any due date falling on a weekend or county holiday to the following business day.

What to do this week

Read the county's file on your house before anything else. It is free, it is online, and it takes about twenty minutes. The description in that file is what the value was built from, so if the description is wrong the value may be too — and a factual error is the strongest kind of appeal there is. How to check your property record for errors walks through it field by field.

Then look at what sold nearby. Not asking prices, and not what a website estimates your house is worth — actual recorded sales, of properties genuinely like yours, that closed early enough to count. Which comparable sales the county will accept covers which ones qualify.

Know that it can go either way. Filing reopens your assessment, and the value can be affirmed, lowered, or raised. Can your assessment go up if you appeal? explains how that works at each route.

If you decide to go further, how to appeal your Fairfax County assessment covers the whole process.

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