Maryland, rather than Montgomery County government, administers real-property assessment appeals. An owner receiving a Montgomery assessment notice has 45 days from the notice date to request a Supervisor's-level appeal through the local SDAT office. The initial conference may be by phone, video, in person, or writing. SDAT provides the owner a property worksheet and area sales listing without charge before the scheduled appeal. FairPath can organize those official materials with owner-selected sales and condition records into a manual packet. The owner must confirm the notice date, submit the appeal, state the disputed total market value, choose the conference format, and pursue any later level within its separate deadline.
Assessment context: Montgomery is reassessed on Maryland's triennial cycle by geographic groups, and increases generally phase in over three years. Review the notice for new market value, phased assessment, effective year, appeal deadline, account, land and improvements, and reassessment area. Bethesda and Chevy Chase, Silver Spring, Rockville, Gaithersburg, downcounty transit areas, upcounty suburbs, agricultural reserve parcels, and rural communities are not interchangeable. School assignment, Metro access, traffic, lot utility, conservation restrictions, historic designation, floodplain, septic service, accessory units, renovation, and condition can affect value. The appeal should address total market value and correct property facts, not merely the tax rate, phased amount, or tax bill.
Filing process: Use the form included with the notice, Maryland's appeal service, or the Montgomery SDAT office at 30 West Gude Drive, Suite 400, Rockville. File within 45 days of the notice date and retain confirmation. Request the free property worksheet and area sales analysis, then review building area, quality, age, condition, land, and comparable selection before the Supervisor's conference. SDAT issues a final notice after first-level review. A dissatisfied owner generally has 30 days from that final notice to appeal to the county Property Tax Assessment Appeal Board. A petition for review or new-owner appeal is a separate route with specific qualifications; do not use it to revive an expired ordinary notice appeal without confirmation.
Evidence to review: Start with the SDAT worksheet and identify factual errors. Select sales from the same submarket and valuation period, addressing school area, transit, municipality, lot, living area, age, quality, renovation, parking, accessory space, view, easements, historic or agricultural restrictions, utilities, and condition. Add photographs, inspection reports, contractor bids, permits, surveys, appraisals, settlement documents, and flood or conservation maps where relevant. Maryland's three-year phase-in and Homestead Tax Credit can affect the bill without proving market value. State an owner opinion of total market value and reconcile the official area sales and any alternative comparables to that figure in an indexed, source-labeled packet.
Current deadline guidance: 45 days from the assessment notice date. A Montgomery County owner must file the first-level appeal with the local Maryland SDAT assessment office within 45 days of the date on the assessment notice. Later review and new-owner routes have separate eligibility and deadlines.
Montgomery appeals are administered by Maryland SDAT through its Rockville assessment office.
The first-level deadline is forty five days from each assessment notice, not one countywide calendar date.
SDAT provides the owner's worksheet and an area sales listing without charge before the appeal.
Triennial reassessment and phased increases must be separated from the total new market value under review.
Official filing authority: Maryland SDAT Montgomery County Assessment Office. https://assessmentappeals.dat.maryland.gov/start.aspx
Source: Maryland Department of Assessments and Taxation, Homeowner's Guide to Property Tax, https://dat.maryland.gov/realproperty/pages/homeowners-guide.aspx. Reviewed 2026-07-16.
Source: Maryland Department of Assessments and Taxation, Montgomery County Reassessment Areas, https://dat.maryland.gov/realproperty/Pages/Montgomery-County-Reassessment-Areas.aspx. Reviewed 2026-07-16.
Source: Maryland Department of Assessments and Taxation, Petition for Review or New Owner Appeal, https://dat.maryland.gov/Documents/Accessible%20Documents/Real%20Property%20Miscellaneous%20Forms/Petition%20for%20Review%20or%20New%20Owner%20Appeal%20of%20Real%20Property_0426-A.pdf. Reviewed 2026-07-16.