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

Direct answer: Montgomery County’s 2026 regular reassessment was for Area/Group 2 properties; SDAT mailed those notices on December 30, 2025, and the 45-day appeal deadline was February 13, 2026. As of July 20, 2026, that window has closed; the next fixed residential filing deadline is January 4, 2027 for a Petition for Review for the next tax year, filed with the Montgomery County SDAT assessment office at 30 W. Gude Drive, Suite 400, Rockville, MD 20850, or by using SDAT’s official appeal portal when you have a reassessment notice control number. (dat.maryland.gov)

How assessments work in Montgomery County

Montgomery County does not set your assessment. The Maryland State Department of Assessments and Taxation (SDAT) values real property statewide, and Montgomery County then applies tax rates and credits to the value certified by SDAT. Maryland reassesses property once every three years by dividing each county into three areas; Montgomery’s Area 2 was effective January 1, 2026, Area 3 is next effective January 1, 2027, and Area 1 is next effective January 1, 2028. (dat.maryland.gov)

For residential property, SDAT uses a blend of the sales approach and cost approach. Land is mainly valued from sales; the dwelling is estimated from cost rates and adjusted by a neighborhood adjustment factor based on sales of similar homes in similar market areas. The number to focus on is the Total New Market Value on the notice—not your tax bill, not last cycle’s value, and not the percentage increase. (dat.maryland.gov)

The 2026 Montgomery Group 2 reassessment was not small: SDAT reported Montgomery residential full cash values rising from $63.779 billion to $71.839 billion, a 12.6% increase, and 76,484 of 90,388 improved residential properties increased in value. Increases are phased in over three years, while decreases take full effect for the 2026 tax year. (dat.maryland.gov)

Whether you should appeal

Appeal if you can show the market value is too high. The strongest Montgomery County arguments are usually: SDAT has the wrong square footage, bathrooms, basement finish, condition, or lot characteristics; nearby comparable homes sold for less; or your property has defects a buyer would price in, such as drainage, foundation, access, or severe deferred-maintenance issues.

Do not spend your 15-minute hearing arguing that taxes are too high, schools cost too much, your value rose too fast, or your neighbor’s percentage increase was lower. SDAT specifically says those are not relevant appeal issues. (dat.maryland.gov)

No official Montgomery County homeowner success rate or median reduction appears to be published by SDAT or PTAAB. The closest current official workload data is statewide/board data: as of December 1, 2025, the Montgomery County Property Tax Assessment Appeals Board had 762 backlogged cases and one vacancy; PTAAB’s statewide 2024 clearance rate reached 120%, but pending cases remained a concern. (mgaleg.maryland.gov)

Before appealing, also check credits. Montgomery’s Homestead cap is 10% for owner-occupied principal residences, but you must have a Homestead Tax Credit application on file; the reassessment notice shows your principal-residence and Homestead status. The State Homeowners’ Property Tax Credit is income-based, requires an annual application, has an October 1 deadline, and is best filed by April 15 so it can appear on the July bill. Montgomery also has a 65+ / retired military credit that can provide a 20% credit on County property taxes for up to seven years if you meet the ownership, age, military, and assessment limits. (dat.maryland.gov)

Step-by-step how to file

1. Find your filing path. If you received a 2026 Notice of Assessment, the regular appeal had to be filed within 45 days of the notice date; for the December 30, 2025 mailing, that was February 13, 2026. If you missed it and your property is not in its reassessment year, use the Petition for Review or New Owner Appeal of Real Property for the next tax year by the first working day after January 1—January 4, 2027. If you bought a property transferred after January 1 and before July 1, you get 60 days from transfer to file a new-owner appeal, but the deed must be recorded. (dat.maryland.gov)

2. Use the correct form. For a current reassessment notice, use SDAT’s Real Property Assessment Appeal Form online portal with the control number on your notice, or return the paper appeal form included with the notice. For out-of-cycle and new-owner cases, use Petition for Review or New Owner Appeal of Real Property. (assessmentappeals.dat.maryland.gov)

3. Choose your hearing option. SDAT allows four options: Written Appeal, Phone Hearing, Video Hearing, or In-Person Hearing. The petition form lets you select the same options; video hearings use Google Meet and require a clear email address. (dat.maryland.gov)

4. File with the Montgomery SDAT office. Mail or deliver paper filings to: Montgomery County Assessment Office, 30 W. Gude Drive, Suite 400, Rockville, MD 20850. The office is open 8:00 a.m.–4:30 p.m.; phone 240-314-4510; email sdat.mont@maryland.gov. For reassessment notices, the official online portal is the cleanest method because it uses your notice control number. (dat.maryland.gov)

5. Pay nothing to file. SDAT says it never charges property owners to file an assessment appeal or obtain their property assessment worksheet. PTAAB and Maryland Tax Court appeals also have no filing fee, although SDAT may charge a nominal fee for worksheets of comparable properties beyond the free worksheet and area sales listing it provides. (dat.maryland.gov)

What happens after

The first level is the Supervisor’s level at SDAT. It is informal and is conducted by an assessor designated by the Montgomery County Supervisor of Assessments. SDAT says these hearings typically take about 15 minutes. Before the hearing, SDAT provides a free property worksheet and Area Sales Listing; written-appeal filers also receive this information. For reassessment appeals, SDAT attempts to complete all hearings by June 1, depending on local volume. (dat.maryland.gov)

After SDAT considers your evidence, you receive a final notice. If you disagree, you have 30 days from that final notice to appeal to the Property Tax Assessment Appeals Board—specifically the Montgomery County board. PTAAB is separate from SDAT; its members are local residents recommended locally and appointed by the Governor. You may appear in person or appeal in writing, and there is no fee. (dat.maryland.gov)

If you lose at PTAAB, you may appeal to the Maryland Tax Court within 30 days of the PTAAB order. Tax Court is more formal, requires you to be present, and hears the matter de novo, meaning the prior result is not treated as controlling. (dat.maryland.gov)

Local tips

Build your packet around three to five sales from the same neighborhood or school-market area, ideally before the valuation date reflected by your reassessment. Use SDAT Real Property Search, not automated online estimates. Highlight concrete differences: living area, lot size, condition, garage, basement finish, renovation level, and whether the sale was arms-length.

Check your tax class and districts before estimating savings. A typical nonmunicipal Montgomery homeowner may see County, State, transit, fire, recreation, and M-NCPPC rates. For FY 2027, current rates include General County/MCPS/College 0.6706, MCPS supplement 0.0470, State 0.1120, transit 0.0828, fire 0.1196, recreation 0.0329, M-NCPPC advance land acquisition 0.0010, Metro District 0.0650, and Regional District 0.0212 per $100, before any municipal or urban-district add-ons. That totals about $1.1521 per $100 for a common nonmunicipal example, but your bill may differ. (apps.montgomerycountymd.gov)

Worked example: suppose your 2026 reassessment says your Kensington-area home is worth $850,000, but three comparable sales support $800,000. A $50,000 reduction saves about $576 per year at a $1.1521 per $100 combined rate: $50,000 ÷ 100 × 1.1521 = $576.05. Because Maryland phases in increases over three years and applies Homestead credits for eligible principal residences, your first-year cash savings may be smaller than the full-market-value math—but the corrected value can still matter across the full cycle and at the next reassessment. (dat.maryland.gov)