Montgomery county property tax: rates, assessments, and how to appeal

Last updated 2026-07-09

How does Montgomery County property tax work?

Two separate government bodies build your Montgomery County tax bill, and neither one is the other. The state of Maryland decides what your property is worth. The county (and your town, if you live in one) sets the rate applied to that value. Homeowners who call the county to argue about their assessment are calling the wrong office, which wastes the two weeks they can't afford to lose.

The Maryland State Department of Assessments and Taxation (SDAT) reassesses every property on a three-year cycle ^[1]. Roughly one-third of properties statewide get a new notice each January. If your property sits in Group 2 or Group 3, your next assessment may not land until 2026 or 2027, even if prices on your street jumped last spring.

Once SDAT sets your full cash value, the county applies its rate. For fiscal year 2024, the county-wide rate is $1.0000 per $100 of assessed value ^[2]. Maryland assesses residential property at 100% of market value (full cash value), so the arithmetic is clean: a $500,000 assessment produces a $5,000 county bill before credits. Municipalities like Rockville or Gaithersburg add their own rate on top, usually somewhere between $0.24 and $0.63 per $100 ^[2].

The property tax is the biggest recurring cost most homeowners carry. Knowing exactly how each layer of the number gets stacked is the first step toward knocking it down.

What are the current Montgomery County MD property tax rates?

The county-wide rate for fiscal year 2024 is $1.0000 per $100 of assessed value, and your town, if you have one, adds its own rate on top ^[2]. The county council votes on rates every year, so treat the table below as FY2024 and verify against the current budget before you calculate anything.

Jurisdiction	Rate per $100 AV	Notes
County-wide	$1.0000	Applies to all unincorporated and incorporated areas
City of Rockville	+$0.6270	Added on top of county rate
City of Gaithersburg	+$0.2600	Added on top of county rate
Town of Chevy Chase	+$0.0840	Added on top of county rate
City of Takoma Park	+$0.5630	Added on top of county rate
City of Barnesville	+$0.1400	Added on top of county rate

A Rockville owner with a $600,000 assessment pays roughly $9,762 a year ($1.6270 x $6,000) before credits. Cross an invisible municipal line into an unincorporated neighborhood a half-mile away, same house, same value, and the bill drops to $6,000. The address does the damage.

Maryland caps how fast an assessment increase reaches your bill. The Homestead Tax Credit limits the taxable assessment increase to 10% per year on owner-occupied principal residences ^[3]. It's separate from the assessment itself, and it applies automatically once you register. Plenty of owners never register, so they never get the cap.

Compare that to Loudoun County, Virginia, where effective rates run around 0.87 to 1.0% and reassessment happens every year instead of every three. Loudoun owners feel market swings faster in both directions. Neither system clearly favors taxpayers. Maryland's triennial cycle can delay a painful increase, but it also delays your relief when the market drops.

How does Montgomery County MD property tax assessment work?

SDAT does not send someone to walk through your house. Assessors run a mass appraisal model, building neighborhood value models from recorded deed sales and then adjusting for square footage, lot size, age, condition, and permits ^[1]. The output is a full cash value meant to track what your property would fetch on the open market. Models make mistakes at the individual level constantly, and that gap is where your appeal lives.

Your January notice shows two numbers: the full cash value and the phased-in value. Maryland phases increases in over three years, so a $90,000 jump raises the assessable base by $30,000 each year of the cycle ^[1]. Decreases are different. They hit right away.

SDAT runs a Montgomery County sub-office in Rockville that handles the county's appeals. Contact details shift from time to time, so pull the current listing from SDAT's office locator instead of trusting a third-party page ^[1].

Here's the confusion that trips people up. Your tax bill uses the phased-in value, not the full cash value. If SDAT calls your house worth $700,000 but the phased-in value is $640,000, you're taxed on $640,000 this year. That changes the appeal math entirely. If the phased-in value already sits below true market value, winning an appeal on full cash value might save you nothing until later years of the cycle.

When is the deadline to appeal a Montgomery County property tax assessment?

You have 45 days from the date printed on your Notice of Assessment to file an appeal ^[4]. The clock starts on the notice date, not the day the envelope reaches your mailbox. SDAT mails notices in late December and early January, and most Montgomery County owners see theirs in the first two weeks of January. A notice dated January 3 gives you until roughly February 17.

Miss the 45 days and you're usually done for that cycle. Maryland allows a discretionary supervisory-level review as a fallback, but it's hard to get and you shouldn't count on it.

Appeal stage	Deadline	Who hears it
First-level (SDAT)	45 days from notice date	SDAT assessment supervisor
Property Tax Assessment Appeals Board (PTAAB)	30 days after first-level decision	Local PTAAB (three-member panel)
Maryland Tax Court	30 days after PTAAB decision	Administrative law judge
Circuit Court	30 days after Tax Court decision	Full judicial review

Most homeowners settle at the SDAT or PTAAB level. Residential cases rarely reach the Maryland Tax Court, and Circuit Court appeals are almost unheard of for a single-family home ^[9]. Build your strongest evidence file for PTAAB and you probably never see the higher rungs.

You can also appeal during the "off years" of your cycle if a recent arm's-length sale of your property shows the assessment is wrong ^[4]. That door exists because markets move faster than a three-year clock.

What evidence actually wins a Montgomery County property tax appeal?

Comparable sales win. Everything else is decoration. You need recent arm's-length sales of properties genuinely like yours, ideally within the last 12 months and within a mile or two. Genuinely like yours means close on square footage, lot size, age, condition, and style. A 1,950 sq ft colonial from 1988 is not a comp for a 2,400 sq ft craftsman from 2005, even if they share a block.

The assessor pulls from the same sales database you can. Your job is to find where the model got your specific house wrong: it missed the busy road behind your fence, counted a below-grade finished basement at above-grade rates, or never saw the failing roof.

A strong appeal file has four things:

• Three to six comparable sales, printed from SDAT's real property search or a licensed Realtor's CMA, with a short adjustment grid explaining why each comp points to a lower value.
• Photographs of deferred maintenance, functional obsolescence, or bad site conditions.
• Your settlement sheet, if you bought recently at a price under the assessed value.
• Any appraisal you already own from a refinance, estate, or purchase. You do not need to commission one for a first-level appeal.

The evidence and comps approach that works in Montgomery County is the same framework used everywhere. King County, WA and DeKalb County, GA hearings run on the same comparable-sales logic.

For DIY filers, TaxFightBack's appeal kit walks you through the comparable grid and the adjustment narrative so you skip the contingency firm that keeps 30 to 40% of your savings.

Don't walk in with a Zillow printout and a grievance about your bill. The supervisor has seen that a thousand times. Show the math.

What exemptions and credits can lower your Montgomery County property tax bill?

Several programs push your effective bill well below the base rate, and most need a one-time application that then continues automatically. The one you're most likely to be missing is the Homestead credit, because it protects you but doesn't announce itself.

Homestead Tax Credit. Owner-occupants of a principal residence register once and the credit caps the annual increase in taxable assessment at 10% statewide ^[3]. The county applies its own 10% cap too. You apply through SDAT's online portal, and it renews automatically. Buy in the last few years and never register, and you've been paying without this protection.

Homeowners' Tax Credit (income-based). Maryland's circuit breaker credit caps property taxes at a percentage of gross income for lower and moderate-income owners ^[5]. The 2024 program income limit is $60,000 for most households, with some exceptions, and the state pays the county the difference. Applications are due September 1.

Seniors. Montgomery County gives a 20% property tax credit to owner-occupants age 65 or older who have lived in the home at least 10 years and meet income limits ^[6]. It's separate from the state Homeowners' Tax Credit and stacks on top of it.

Veterans. A veteran with a 100% permanent and total service-connected disability rating gets a full property tax exemption on a Maryland principal residence ^[7].

Agricultural land preservation. Rural properties enrolled in agricultural use assessment get taxed on farm value instead of full market value, which can be far lower.

Only the Homestead credit runs on its own, and only after you register the first time. Everything here starts with a form.

How does Montgomery County compare to other high-value suburban counties?

Montgomery County sits with a group of affluent suburbs where high assessed values and moderate rates combine into large annual bills. The table uses effective rates (taxes paid divided by market value) instead of nominal rates, because assessment ratios differ from state to state.

County	State	Effective tax rate (approx.)	Reassessment cycle
Montgomery County, MD	Maryland	~1.05 to 1.10%	Triennial
Loudoun County, VA	Virginia	~0.87 to 1.0%	Annual
Orange County, CA	California	~0.65 to 0.75%	Change-of-ownership triggered [8]
King County, WA	Washington	~0.90 to 1.05%	Annual
DeKalb County, GA	Georgia	~1.0 to 1.2%	Annual

Orange County, CA runs under Proposition 13, which caps annual increases at 2% until a sale resets the value to the purchase price ^[8]. That's why orange county property taxes behave so differently in practice. A long-term owner in Newport Beach can pay an effective rate under 0.5% while the new buyer next door pays on today's market value. Montgomery County has no purchase-price lock. The triennial reassessment tracks the market for everybody.

The OC property tax comparison shows why Maryland owners feel the market more directly. California protects incumbents and creates wide gaps between neighbors. Maryland hits everyone more evenly, then delivers sudden jumps when a triennial reassessment catches up to a hot market.

How do I file a Montgomery County property tax appeal myself?

A first-level appeal in Maryland is free, and you can file it by mail, online, or in person. Here's the process step by step.

Step 1: Read your notice closely. You're appealing the full cash value. Write down the notice date, because your 45-day clock starts there.

Step 2: Pull comparable sales from SDAT's real property search at sdat.dat.maryland.gov ^[1]. Search nearby homes with similar characteristics and look at recorded sale prices from the past 12 to 18 months. You want sales below your assessed value. Print or export them.

Step 3: Build a simple adjustment grid. List each comp. Where your property is inferior, add value to the comp; where it's superior, subtract. If your adjusted comps consistently land below your assessment, you have a case.

Step 4: Complete the appeal form that came with your notice or download it from SDAT. The form asks for your opinion of value and your evidence. Be specific.

Step 5: File before the 45-day deadline. SDAT schedules a supervisor conference, usually within 60 to 90 days. Bring your comps and photos, and hand over a paper packet the supervisor can keep. A packet beats a verbal argument every time.

Step 6: If the result disappoints you, file the PTAAB appeal within 30 days. It's a more formal hearing but still built for owners without a lawyer.

A residential first-level appeal takes maybe 4 to 8 hours of prep if you do it right. That's a fair trade when a win might cut $500 to $2,000 a year. Contingency firms usually take 30 to 40% of the first year's savings, so on a $1,200 reduction they keep $360 to $480 and you only see full benefit in year two. Do it yourself with a structured framework and you keep 100% from day one.

What is the Montgomery County property tax payment schedule?

Montgomery County splits the annual bill into two semi-annual installments ^[2].

Installment	Due date	Covers
First half	September 30	First half of fiscal year
Second half	December 31	Second half of fiscal year

Late payments accrue interest at 1.5% per month on the unpaid balance ^[2]. Let taxes go unpaid for two years and the property becomes eligible for the county's tax sale, held each May for delinquent prior-year balances.

You can pay online through the county tax portal, by mail, in person at the Division of Treasury, or through an escrow account if your mortgage servicer pays for you. If a servicer pays, verify the payment actually went out. Servicer errors happen, and the penalty lands on the property owner, never the servicer.

Win an assessment appeal after you've already paid on the higher value, and you get a refund for the overpayment. Expect it to take 90 to 180 days to process once the appeal is final.

Can I look up any property's assessed value in Montgomery County?

Yes. Maryland's SDAT real property search is one of the more open assessment databases in the country ^[1]. Search by address, owner name, or parcel ID at sdat.dat.maryland.gov and you'll see the full assessment history, tax maps, and legal description for any parcel. No login.

The record shows the current full cash value, the phased-in value for each year of the cycle, the prior cycle's values, and any credits already applied. It also shows the land-to-improvement split, which can expose errors. If your land is valued at $350,000 and your improvement at $85,000 for a 2,400 sq ft home in a good neighborhood, something's wrong.

For sale prices to build your comps, the Maryland Land Instruments search at mdlandrec.net shows recorded deeds with prices ^[10]. Run both databases together and you have what a professional appraiser starts with.

Curious how other states handle transparency? Sedgwick County, KS and DeKalb County, GA both keep searchable assessment databases, though the depth of history varies.

What happens if my appeal is denied at every level?

Losing at all four levels (SDAT supervisor, PTAAB, Maryland Tax Court, Circuit Court) is rare for a well-built case, but it happens. When it does, your realistic option is to wait for the next triennial reassessment and file again with stronger evidence.

One door people forget: if you sell the property during the triennial cycle, you can use the settlement price as grounds for an immediate reassessment appeal in the off year ^[4]. Maryland's Tax-Property Article Section 14-502 ties the right to review to an arm's-length sale. Buy your home this year at $480,000 while the assessment sits at $540,000, and that purchase price is the strongest evidence you can hold.

A Circuit Court appeal effectively requires an attorney, and the filing costs alone can run into the thousands. For most homes the economics don't justify going that far unless the assessed value is badly wrong and the annual savings are large.

After a denial, the smart next move is to recheck your credits. A lot of owners leave the Homestead or senior credit unclaimed. Then recalculate whether the phased-in value already closes most of the gap, so the real overpayment is small. Sometimes the bill looks worse than the math actually is.

Frequently asked questions

What is the Montgomery County MD property tax rate for 2024?

The county-wide rate for fiscal year 2024 is $1.0000 per $100 of assessed value. Municipal areas add their own rates on top: Rockville adds $0.6270, Takoma Park adds $0.5630, and Gaithersburg adds $0.2600. Your total rate depends on where in the county you live. Confirm the current year's rate with the county's Department of Finance, since the council votes on rates annually.

How often does Montgomery County reassess property values?

Maryland SDAT reassesses on a triennial (every three years) cycle, not annually. Roughly one-third of all properties statewide get a new Notice of Assessment each January. When your assessed value rises, the increase phases in over three years at one-third per year. Decreases in value take effect immediately rather than phasing in.

What is the deadline to appeal a Montgomery County property tax assessment?

You have 45 days from the date printed on your Notice of Assessment. The clock starts on the notice date, not the day it arrives. Notices typically go out in late December or early January. Missing this deadline is nearly always fatal to your appeal for that cycle. If you miss it, you may still appeal in an off year if a recent arm's-length sale proves the assessment is wrong.

How do I apply for the Maryland Homestead Tax Credit in Montgomery County?

Register once through the SDAT online application at sdat.dat.maryland.gov. You must own and occupy the property as your principal residence. Once approved, the credit caps your annual taxable assessment increase at 10% per year and renews automatically. Many owners who bought years ago never registered and are missing this protection right now.

Does Montgomery County offer a property tax break for seniors?

Yes. Montgomery County gives a 20% property tax credit to owner-occupants who are 65 or older, have lived in the property at least 10 consecutive years, and meet income thresholds. This is a county-level credit on top of the state Homeowners' Tax Credit. You must apply through the county; it does not apply automatically.

Can I appeal my Montgomery County property tax assessment myself without a lawyer?

Yes, and most homeowners should. The first-level SDAT supervisor conference and the PTAAB hearing are both built for self-represented owners. You need comparable sales, a clear adjustment grid, and photos of relevant conditions. A contingency firm costs 30 to 40% of your first year's savings. A structured DIY approach keeps all of it, and prep runs about 4 to 8 hours for a residential property.

What comparable sales should I use for a Montgomery County appeal?

Use recent arm's-length sales (within 12 to 18 months ideally, no more than 24 months) of properties similar in size, age, condition, style, and location. Pull sales from SDAT's real property search and Maryland's land records database. Avoid foreclosures, estate sales, and related-party transfers, since assessors can challenge those as not arm's-length. Three to six strong comps beat a dozen weak ones.

How is Montgomery County MD different from Orange County CA property tax?

Orange County, CA runs under California's Proposition 13, which locks assessed value at the purchase price and caps annual increases at 2% until the property sells. Montgomery County, MD has no purchase-price lock. SDAT reassesses every three years at current market value, so all owners face market-rate increases regardless of how long they've owned. The systems produce very different outcomes for long-term owners.

When are Montgomery County property tax bills due?

The annual bill splits into two installments: the first half is due September 30 and the second half is due December 31. Late payments accrue interest at 1.5% per month. Properties with two years of unpaid taxes become eligible for the county's annual tax sale held each May. You can pay online, by mail, or in person at the Division of Treasury.

What is the Maryland Homeowners' Tax Credit income limit?

Maryland's Homeowners' Tax Credit (the state income-based circuit breaker) has a gross income limit of $60,000 for most households as of the 2024 program year, with some variation for different household sizes. The program caps property taxes at a percentage of gross income, and the state pays the county the difference. The annual application deadline is September 1.

Can I look up my neighbor's property assessment in Montgomery County?

Yes. Maryland's SDAT real property search at sdat.dat.maryland.gov is a public database. Search any parcel by address, owner name, or parcel ID and see current assessed value, assessment history, and property characteristics. No account or subscription needed. This is the same data you'd use to find comparable properties for an appeal.

Does a 100% disabled veteran pay property tax in Montgomery County?

No. Maryland state law provides a full property tax exemption for the owner-occupied principal residence of a veteran with a 100% permanent and total service-connected disability rating from the U.S. Department of Veterans Affairs. You must apply through SDAT; it is not automatic. Surviving spouses of qualifying veterans may also be eligible.

How does the phased-in assessment value affect my appeal strategy?

You appeal the full cash value (market value), but your bill uses the phased-in value. If your full cash value is $700,000, your phased-in value this year is $620,000, and your evidence suggests $660,000, then winning an appeal to $660,000 saves you nothing this year. Calculate both numbers before deciding whether the appeal is worth your time.

Sources

1. Maryland State Department of Assessments and Taxation (SDAT), Real Property Assessment Process: SDAT reassesses all Maryland real property on a triennial cycle; notices are mailed each January
2. Montgomery County, MD, Department of Finance, Real Property Tax Rates FY2024: County-wide rate is $1.0000 per $100 AV for FY2024; municipal rates and due dates of September 30 and December 31
3. Maryland SDAT, Homestead Tax Credit Program: Homestead Tax Credit caps annual taxable assessment increases at 10% for owner-occupied principal residences
4. Maryland General Assembly, Tax-Property Article, Section 14-502: 45-day appeal deadline from notice date; arm's-length sale triggers off-cycle appeal right
5. Maryland SDAT, Homeowners' Tax Credit Program: Maryland Homeowners' Tax Credit income limit of $60,000 for 2024; September 1 annual application deadline
6. Montgomery County, MD, Department of Finance, Senior Property Tax Credit: Montgomery County offers a 20% property tax credit for owner-occupants age 65 and older meeting income and residency requirements
7. Maryland SDAT, Disabled Veterans Property Tax Exemption: 100% permanently and totally disabled veterans receive a full property tax exemption on their principal residence in Maryland
8. California State Board of Equalization, Proposition 13 Overview: Proposition 13 caps California assessed value at purchase price with 2% annual increase cap until change of ownership; applies to Orange County CA properties
9. Maryland Judiciary, Maryland Tax Court: PTAAB and Maryland Tax Court provide additional levels of appeal after SDAT first-level review; 30-day filing windows at each stage
10. Maryland Department of Land Records, MDLandRec.net: Recorded deeds with sale prices are publicly searchable for use as comparable sales evidence in Maryland assessment appeals