Dread on Arrival

Start by making sure the assessors have the correct physical description of your home, including the proper square footage and the correct number of bathrooms and bedrooms. If they are mistaken, these are relatively easy details to confirm. For instance, if the records show you have three bathrooms and in reality there are only two, fixing the error can knock tens of thousands of dollars off the value, assessors said.

Assessors do not go inside a home unless invited. So a homeowner should tell them about what they cannot see, including the leaky basement, the crack in the foundation and other problems that one assessor described as "incurable."

"This is the only time we have an opportunity to hear and see what goes on inside the house," said C. John Sullivan, director of Maryland's Department of Assessments and Taxation, which mailed out 661,000 notices. "We will take a look, and we allow depreciation for things over and above the normal wear and tear."

The assessment is based not only on the physical attributes of the house, but also on how it compares to other nearby houses of a similar age, quality and style. If your assessment is way out of line with that of these comparable houses, that can be grounds for an appeal.

The assessment on every house is public information and available on government Web sites. To find houses comparable to yours, start by looking at those closest, advised Daniel Ercolani, supervisor of assessments in Montgomery County. "Start with the street, and if there's nothing, then go to the general subdivision. . . . Go as far as you have to until you find a house similar in size and quality, and then make adjustments for location."

Historically, only a tiny percentage of homeowners have appealed their taxes in most jurisdictions.That appears to be the pattern so far in the areas that have sent notices.

Alexandria resident Bob Soltys figures that many people shy away from the process because it's somewhat intimidating. "Many people think they can come out worse as opposed to better, and that was not my experience," said Soltys, 67.

That experience has involved about five appeals since Soltys moved into his home in 1998. Three times, the appeal worked in his favor, though his assessment was not lowered much in each case.

"I did find errors and I don't think those errors were intentional, but they somehow crept into the system," Soltys said.

In any case, if errors exist, they should be fixed, even if the financial gains seem minimal from a homeowner's perspective, said Cindy Smith-Page, director of real estate assessments for Alexandria.

"If it's an error, it's worth asking for a review," Smith-Page said. "You don't want to perpetuate even a $100 error into the future, because $100 this year is $100 next year and the year after that."

Besides, look at it this way, said James P. Soresi, supervisor of assessments for Prince George's County: "You can always cancel an appeal, but you can't always appeal after the deadline passes."

For more information on local assessment schedules, tax rates, contacts and more, check these two documents (in PDF format):

D.C. and Virginia Residents

Maryland Residents