How to Appeal Property Taxes in Baltimore County, Maryland (2026 Guide)

For Baltimore County’s 2026 reassessment, Area 2 assessment notices were mailed December 30, 2025, so the standard 45-day reassessment appeal deadline was February 13, 2026. As of July 25, 2026, the next fixed deadline for a Baltimore County homeowner who missed the reassessment appeal window is a Petition for Review due January 4, 2027 for the tax year beginning July 1, 2027; file it with SDAT’s Baltimore County Assessments office in Towson.

File online if you are appealing a current reassessment notice through SDAT’s Real Property Assessment Appeal Form. Otherwise use the paper Petition for Review or New Owner Appeal of Real Property and submit it to Baltimore County Assessments, Hampton Plaza, 300 E. Joppa Road, Suite 602, Towson, MD 21286, or email sdat.blco@maryland.gov when your notice/form instructions allow email.

How assessments work in Baltimore County

Baltimore County assessments are set by the Maryland State Department of Assessments and Taxation, not by Baltimore County government. SDAT values real property at market value and maintains the assessment roll; Baltimore County then applies tax rates and issues/collects tax bills.

Maryland uses a three-year reassessment cycle. Baltimore County is split into three reassessment areas: Area 1 was effective January 1, 2025 and is next reassessed January 1, 2028; Area 2 was effective January 1, 2026; Area 3 was effective January 1, 2024 and is next reassessed January 1, 2027. SDAT’s 2026 statewide reassessment was the Group 2 cycle. The notices were mailed December 30, 2025, and SDAT reported Baltimore County Group 2 residential values rose about 12.4% from the January 1, 2023 base to January 1, 2026.

A higher market value is not always the same as an immediately higher taxable value. Assessment increases are phased in evenly over three years. If the property is your principal residence and your Homestead Tax Credit is approved, Baltimore County’s local Homestead cap for July 1, 2026 is 4%, while the state cap is 10%. That means many owner-occupied homes are taxed on a capped taxable assessment even if the market assessment rose faster.

Whether you should appeal

Appeal if the Total New Market Value is higher than what your house was worth on the relevant January 1 valuation date, or if SDAT’s property data is wrong. Good Baltimore County appeal issues include: incorrect finished living area, wrong bath count, basement finish overstated, condition problems not reflected, non-buildable or constrained land, or better comparable sales in your neighborhood.

Do not base the appeal on “my taxes went up,” “my increase is bigger than my neighbor’s,” or county services. SDAT says the appeal is about the total market value of the land and improvements together.

Start with SDAT’s Real Property Data Search. Look up your property and three to five comparable sales in the same subdivision or nearby part of the county—Catonsville comps are usually more useful for Catonsville than Owings Mills or Perry Hall. Use arms-length sales as close as possible to the valuation date. For the 2026 reassessment, that means sales before or near January 1, 2026 are stronger than later 2026 sales.

SDAT’s statewide FY 2025 annual report publishes statewide appeal workload numbers, not a Baltimore County homeowner success rate or median reduction. The useful takeaway is practical: do not assume a reduction is automatic; bring specific valuation evidence.

Step-by-step how to file

1. Identify your appeal type. If you received a reassessment notice, use the appeal form/online system within 45 days of the notice date. For the December 30, 2025 Area 2 notices, 45 days made the deadline February 13, 2026. If you bought a property transferred after January 1 but before July 1, use the new-owner appeal within 60 days from the transfer date. If you are outside the reassessment year, file a Petition for Review for the next tax year.

2. Use the right form. The online form is called Real Property Assessment Appeal Form and requires the county, notice number, and control number from your assessment notice. The paper form for off-cycle and purchase appeals is Petition for Review or New Owner Appeal of Real Property.

3. Choose the hearing option. SDAT offers four first-level choices: written appeal, phone hearing, video hearing, or in-person/personal hearing. The petition form says Google Meet is the supported video platform and that an email address is needed for a video link.

4. Submit to the Baltimore County SDAT office. Mail or hand-deliver paper filings to Baltimore County Assessments, Hampton Plaza, 300 E. Joppa Road, Suite 602, Towson, MD 21286. The office is open Monday-Friday, 8:00 a.m.-4:30 p.m. The phone number is 410-512-4900; fax is 410-321-4148; email is sdat.blco@maryland.gov. Reassessment notices also allow the signed notice appeal form to be returned by mail or email to the local assessment office shown on the notice.

5. Pay no filing fee. SDAT states it does not charge owners to file a real-property assessment appeal or to request a copy of their own property assessment worksheet. Comparable property worksheets may carry a small/nominal fee, so ask the Towson office before ordering a stack.

What happens after

The first level is the Supervisor’s level at the Baltimore County Supervisor of Assessments office. It is informal and usually handled by an assessor designated by the Supervisor. SDAT describes a typical hearing as about 15 minutes. Before the hearing, SDAT provides your property worksheet and an Area Sales Listing at no cost. In the hearing, the assessor reviews the worksheet, explains how the value was developed, and lets you point to errors or comparable sales.

If you choose a written appeal, SDAT reviews the documents without an oral hearing and mails the final notice. The petition form says that after the information is considered, you will be mailed a final notice detailing the result. For regular reassessment appeals, SDAT says it attempts to complete reassessment appeals by June 1, depending on appeal volume.

If you disagree with the Supervisor’s final notice, the next level is the Property Tax Assessment Appeal Board for Baltimore County. PTAAB is independent from SDAT. You have 30 days from the date of the Supervisor’s final notice to appeal to PTAAB. There is no PTAAB filing fee, and you may appear in person or appeal in writing. A PTAAB hearing is a new hearing, so resubmit your evidence rather than assuming the board already has it. If you disagree with PTAAB’s order, you may appeal to the Maryland Tax Court within 30 days; there is no written-hearing option at that level.

Local tips

Check exemptions and credits before spending money on an appeal. For owner-occupied homes, confirm your Homestead Tax Credit status in SDAT Real Property Search; Baltimore County’s 4% local cap can matter more than a small assessment reduction. If household income is limited, review the Homeowners’ Property Tax Credit; the 2026 application deadline is October 1, 2026, and Baltimore County is listed as a county with a supplemental credit administered through the state application. Seniors and retired veterans should also check Baltimore County’s elderly/veteran credit rules, and disabled veterans or blind homeowners should review state/local exemption provisions.

A savings example: suppose SDAT valued an Area 2 Baltimore County house at $430,000, but strong comparable sales support $400,000. A successful $30,000 reduction saves county tax of $330 per year at Baltimore County’s FY 2026 real property rate of $1.10 per $100 of assessed value. Add the Maryland state real property rate of $0.112 per $100, and the total direct annual property-tax savings is about $363.60 before any Homestead cap effects. If the home is owner-occupied and capped, your immediate bill savings may be smaller, but the lower market assessment can still help over the three-year phase-in period.