How Often Should You Check Your Home's Value? Why It Matters for Insurance and Property Taxes in DC and Maryland
The short answer: Check your home's value at least once a year, and every time you get an assessment notice or insurance renewal. Your home actually has three different "values": market value (what a buyer would pay), assessed value (what the tax office thinks it's worth), and replacement cost (what it would take to rebuild). If you lose track of them, you can end up underinsured after a disaster or overpaying property taxes for years. In Maryland, you usually have only 45 days to appeal a new assessment.
What are the three values of your home, and why are they different?
Most homeowners think their house has one number. It actually has three, and each one controls a different part of your finances:
Market value is what a buyer would pay today. It drives your equity, your refinance options, and your sale price.
Assessed value is what SDAT (in Maryland) or the Office of Tax and Revenue (in DC) uses to calculate your property tax bill.
Replacement cost is what it would cost to rebuild your house from the ground up at today's labor and material prices. This is the number your homeowners insurance should be based on. It is not the same as market value.
These numbers drift apart over time, and the gap between them is where homeowners lose money.
Is my home underinsured?
There's a real chance it is. Your dwelling coverage (Coverage A on your declarations page) should reflect what it costs to rebuild, not what you paid or what Zillow says. A lot of homeowners get this wrong, and coverage limits often don't keep pace with construction costs on their own.
Here's what I see in the Route 1 corridor specifically: our older homes often cost more to rebuild than they'd sell for. A 1920s bungalow in Riverdale Park or a Victorian in Hyattsville's historic district has plaster walls, old-growth framing, custom millwork, and details that cost a fortune to recreate. As the owner of an 1884 Hyattsville home myself, I can tell you that a "standard" rebuild estimate doesn't come close for houses like ours. If your policy was written off a generic per-square-foot number, it may fall well short.
How to check your coverage in 15 minutes:
Pull your declarations page and find your Coverage A (dwelling) limit.
Ask your insurance agent for a current replacement cost estimate, and tell them about any renovations, additions, finished basements, or historic features.
Ask whether you have extended replacement cost (adds a cushion above your limit) or inflation guard (raises your limit automatically each year).
Confirm you meet your insurer's coinsurance threshold. Many require coverage of at least 80% of replacement cost, or partial claims get paid out at a reduced rate.
Can I appeal my property tax assessment in Maryland?
Yes. Maryland reassesses every property once every three years, with about a third of homes getting new notices each December. When you get a notice, you have 45 days from the date on the notice to appeal to SDAT. Miss it, and you're generally stuck with that value for the full three-year cycle.
There are three main windows to know:
New assessment notice: 45 days from the notice date (typically mid-February for late-December notices).
Petition for review in a non-reassessment year: deadline is December 31, which is coming up. If you missed your appeal earlier in the cycle, this is your chance to challenge the remaining years.
Recent purchase: if your deed was recorded between January 1 and June 30, you can appeal within 60 days of recording.
Should I bother appealing if I have the Homestead Tax Credit? Often yes. The Homestead credit limits how fast your taxable assessment can rise each year. Prince George's County's cap is 3%, which is far lower than Montgomery County's 10%. But the cap doesn't fix an inflated base value. And here in Hyattsville and other incorporated municipalities, you pay both city and county taxes on that assessment, so an overvaluation costs you twice. Also, make sure your Homestead application is actually on file with SDAT. It's a one-time filing, and plenty of owners assume they have it when they don't.
How do I appeal my property taxes in DC?
DC reassesses every property every year. The first-level appeal goes to your assigned OTR assessor and is due by April 1, or within 45 days of purchase if you bought later. You can file online through MyTax.DC.gov. If you disagree with the result, you have 45 days to take it to the Real Property Tax Appeals Commission. The first-level form is short, so file by the deadline even if you're still gathering evidence.
What evidence wins a property tax appeal?
Assessors respond to data, not frustration. The strongest appeals include:
Three to five recent comparable sales of similar homes nearby that sold for less than your assessed value.
Documentation of condition issues, such as a foundation problem, an original kitchen, or a roof near the end of its life, with photos and contractor estimates.
Errors on your property record, like the wrong square footage, a phantom bathroom, or a basement listed as finished when it isn't. Check your listing on SDAT's Real Property search. Errors are more common than you'd think.
This is exactly the analysis I run for clients. Pulling the right comps is the hard part, and a Realtor who works your neighborhood every week has access to MLS data that the public sites don't show.
Key takeaways
If you own a home:
Review your insurance coverage every year at renewal, especially if you own an older or historic home.
Open every assessment notice the day it arrives and mark the 45-day deadline.
Confirm your Homestead credit is on file.
If you're buying or selling:
Buyers: you get a fresh appeal window after closing, so use it. Also budget for the fact that the seller's capped tax bill won't carry over to you.
Sellers: an inflated assessment can scare buyers who see the tax estimate on the listing. Knowing your real market value helps you price right and address it up front.
Frequently asked questions
How often should I check my home's value?
At least once a year, plus whenever you get an assessment notice or insurance renewal. If you've renovated, check right after the project is done.
Should I insure my home for its market value?
No. Insure it for replacement cost, meaning the cost to rebuild. Market value includes the land, which doesn't burn down, and it moves independently of construction costs.
How long do I have to appeal my property assessment in Maryland?
45 days from the date printed on your assessment notice. New buyers whose deed recorded between January 1 and June 30 get 60 days from recording, and anyone outside a reassessment year can file a petition for review by December 31.
What is the Homestead Tax Credit cap in Prince George's County?
3% per year on your taxable assessment for the county portion, compared to 10% in Montgomery County. You must have an application on file with SDAT to receive it.
When is the DC property tax appeal deadline?
April 1, or 45 days after purchase if you bought later. File online through MyTax.DC.gov.
Can a real estate agent help with a property tax appeal?
Yes. An agent can pull recent comparable sales from MLS, which is the core evidence assessors look for. I prepare comp reports for homeowners across PG County, Montgomery County, and DC.
Not sure what your home is really worth?
I'll put together a free, no-obligation home value report using real local sales. You can use it to check your insurance coverage, decide whether to appeal your assessment, or plan your next move.
Call or text Ryan Hehman at 443-990-1230 or email Ryan.Hehman@compass.com.