What to Do After Your Denver Property Tax Appeal Is Denied
The assessor's denial letter starts a 30-day clock. Miss it and you lose the right to escalate entirely. Here's the exact process, the fees, and what evidence actually moves the Board of Assessment…
The assessor’s denial letter starts a 30-day clock. Miss it and you lose the right to escalate entirely. Here’s the exact process, the fees, and what evidence actually moves the Board of Assessment Appeals.
If you filed a property tax protest this spring and just received a denial notice from the Denver Assessor’s Office, stop and read this before you do anything else. The letter in your hand isn’t the end of the process. It’s the beginning of a separate, more formal one — with a hard statutory deadline that the Colorado legislature has made entirely unforgiving.
Every year, Denver property owners who receive denial letters assume they have until the end of the month, or until they get around to it, or until after vacation. Some of them are wrong by a few days and lose the right to appeal their valuation for that entire tax year. This article tells you exactly what the deadline is, how to calculate it, what it costs to proceed, what evidence actually works at the next level, and whether you need professional help to get there.
The Denial Letter Is a Starting Gun, Not a Stop Sign
The Denver Assessor’s Office mails protest decisions in late June and July for the standard reassessment cycle. Denial letters are arriving in mailboxes right now. Many of the property owners receiving them are treating them as final answers rather than invitations to escalate.
They’re not final. Colorado law provides a structured administrative appeal ladder. The next rung is the Board of Assessment Appeals, a state-level quasi-judicial body that operates independently of the assessor. It reviews property tax disputes from counties across Colorado, hears thousands of cases each year, and can reduce your assessed value. Denver County has generated among the highest BAA petition volumes in the state during recent reassessment cycles — driven by the sharp run-up in residential values between 2020 and 2022. That’s not a coincidence. It’s what happens when an entire city’s assessed values jump 30 to 40 percent in two years.
The BAA is the right forum for property owners who received a denial that felt cursory or unsupported. It’s also the right forum for owners who have stronger evidence now than they did when they filed the original protest. The key legal concept is “de novo review”: the board doesn’t audit the assessor’s process or ask whether the assessor followed procedure. It reconsiders the value of your property from scratch, on the evidence before it. That matters a great deal for how you build your case.
You Have 30 Days — and the Clock Starts on the Date of Mailing
Under C.R.S. § 39-8-108(1), a property owner who wants to appeal a Denver assessor denial to the BAA must file a petition within 30 days of the date the notice of determination was mailed. Not 30 days from when you opened the envelope. Not 30 days from when you received it. Thirty days from the date printed on the notice itself.
This distinction trips up a meaningful number of Denver property owners every cycle. If your denial letter is dated July 7, your BAA petition must be filed — received and filed, not merely postmarked — no later than August 6. If you went out of town for two weeks in July and opened the letter on the 21st, you have 16 days left, not 30. That’s the situation. I’m not trying to be alarmist, but this is genuinely how people lose otherwise valid appeals.
Find the mailing date on your notice right now and write it on your calendar. Count 30 days forward. There are no exceptions under the statute, no hardship extensions, no equitable tolling. The BAA has no discretion to accept late petitions, and it doesn’t exercise any. Once the window closes, the assessor’s determination becomes final for that tax year.
One practical risk: denial letters mailed in late July push the 30-day window into late August, when many Denver families are traveling. If your letter arrived near the end of July, treat the deadline with real urgency.
What It Costs to File and Whether the Math Works
Filing a residential petition with the BAA costs $50. Non-refundable, regardless of outcome. For most mid-range and higher-value Denver properties, the math isn’t close. A $50 filing fee against the potential of hundreds of dollars in annual tax savings makes filing financially viable for essentially any owner in that range. Even if your probability of success is one in three, the expected value of filing is positive.
For a Capitol Hill condo or a Hilltop single-family home at the higher end of Denver’s current market, the potential annual savings from a meaningful value reduction run into the thousands. Fifty dollars is a rounding error.
Commercial and income-producing property carries a higher filing fee — $150 for commercial petitions. The economics of filing almost always justify it, and the stakes typically justify professional representation as well. Confirm the current fee schedule directly with the BAA before filing; these amounts are subject to adjustment.
How to Actually File
The Board of Assessment Appeals is at 1313 Sherman Street, Room 315, Denver, CO 80203. The BAA also maintains an online filing portal. Before you file electronically, confirm with the BAA directly that the portal is accepting petitions for your current assessment cycle — availability changes between cycles without much fanfare.
A completed BAA petition isn’t just a cover sheet with your parcel number. The form requires you to identify the grounds for your appeal, specify the relief you’re requesting (meaning the value you believe is correct), and identify the evidence you intend to submit. That third requirement is the one most DIY filers underestimate. The BAA won’t accept a petition that amounts to “I think my house is worth less” without substantiation. Gather your evidence before you complete the petition form, not after. If you file a bare petition planning to figure out the evidence later, you’ll likely be denied again.
The Evidence That Actually Persuades the BAA
Read your denial letter carefully before you decide what evidence to gather. Denver assessors use fairly consistent denial language, and that language tells you something specific about what the BAA will want to see.
If your denial says something like “the assessed value reflects current market conditions” or “comparable sales support the valuation,” that’s the most common boilerplate dismissal. It means the assessor relied on their own comp set and wasn’t persuaded by yours. Your BAA strategy should be a more thorough, better-documented comparable-sales analysis — ideally 5 to 10 sales of genuinely comparable properties with detailed adjustment documentation. Alternatively, a MAI-certified independent appraisal from a licensed Colorado appraiser carries significant weight with BAA hearing officers. It’s one of the strongest single pieces of evidence you can submit.
When a denial cites “insufficient comparable sales provided,” the assessor is telling you directly that your evidence was thin. Respond with a MAI appraisal. Don’t try to fix this with more amateur comparable-sales research unless you have genuine appraisal expertise. The BAA will weight a professional appraisal above a taxpayer-assembled spreadsheet, and there’s no shame in that — appraisers spend years learning how to do this correctly.
If your denial references the physical condition of the property — or notably doesn’t address it at all — you’re looking at the argument most often left on the table at the protest stage. Property owners rarely document deferred maintenance, functional obsolescence, structural issues, roof age, mechanical system conditions, or the condition advantage of comparables that are in better shape. A formal property condition inspection report from a licensed home inspector, combined with contractor estimates for necessary repairs, can support a meaningful downward adjustment at the BAA. For a closer look at what inspectors commonly find in Denver homes and why it matters for valuation, see what Denver home inspectors flag most often and why it matters here. This evidence is almost never presented at the protest stage and almost always overlooked by the assessor’s mass-appraisal model.
Condo owners in Capitol Hill, Baker, and Five Points face valuation challenges that assessors regularly underweight: high HOA fees that reduce net value, aging building stock with deferred maintenance, special assessments that affect market pricing. If your condo denial ignored your HOA documentation or a pending special assessment, the BAA is the place to make that argument with financial documentation, not just assertion.
Denver’s 2023 reassessment cycle used a June 30, 2022 appraisal date, meaning assessors valued properties based on market conditions as of that date. Denver’s residential market began softening after that point. Owners in Wash Park, LoHi, RiNo, Congress Park, and Hilltop saw the most aggressive reassessment increases — and, correspondingly, the most contentious denials. If your neighborhood saw peak-cycle appreciation baked into the assessed value and you can document that sales in your micro-market were softening by mid-2022, that’s a substantive BAA case. A lot of owners in those neighborhoods have that case and don’t know it.
Written Record or In-Person Hearing
When you file your BAA petition, you’ll choose between a written-record review and an in-person hearing. This is a genuine strategic decision.
Written-record review is faster. You submit your evidence in a written package, the assessor submits their response, and a BAA hearing officer rules on the record. It works well for clean comparable-sales arguments where the numbers tell the story without much context.
In-person hearing is the right choice when your case requires explanation — when you’re challenging the assessor’s methodology rather than just their comp selection, when you have condition evidence that benefits from presentation, or when the property has characteristics that are hard to communicate in writing. In-person hearings also allow you to question the assessor’s appraiser, which occasionally reveals weaknesses in the mass-appraisal analysis. Confirm directly with the BAA whether remote video hearings remain available for the current cycle; procedures in this area have changed in recent years.
One thing worth saying plainly: don’t choose in-person because you’re angry about your denial and want to make your case directly to someone. I understand the impulse — a form letter dismissal after months of waiting is genuinely frustrating. BAA hearing officers are experienced and not susceptible to frustration testimony. Format your choice around your evidence.
Do You Need a Tax Agent or Attorney
The BAA allows self-representation. No attorney or licensed agent is required to file or appear. Many Denver residential property owners handle BAA appeals themselves, particularly for straightforward comparable-sales arguments on single-family homes.
Self-representation makes sense when your property is a single-family home or condo at the lower end of Denver’s value range, your case rests on a clean set of comparable sales, and you’re willing to invest the time to organize evidence and prepare a submission. Your out-of-pocket is likely the $50 filing fee plus the cost of an independent appraisal if you choose to get one.
Professional representation makes sense when your property is at the higher end of the residential market, your case involves methodology challenges or complex condition issues, or you own commercial or income-producing property. That last legitimate reason to hire someone: this takes real time to do properly, and “I don’t have the bandwidth” is a perfectly valid calculation.
Fee structures vary. Many Denver practitioners charge a flat fee for BAA representation — in the range of $300 to $800 for residential work depending on complexity, though rates vary and you should get specifics from any firm you contact. For commercial properties, contingency arrangements are more common, with the practitioner taking a percentage — often 25 to 40 percent — of the first year’s tax savings. Contingency means no upfront cost, but confirm exactly what “savings” means in the agreement. Some contingency contracts calculate savings against the original assessed value; others calculate against the value after the BAA ruling. That distinction matters more than it sounds.
For referrals, the Colorado Coalition of Property Tax Agents maintains a member directory of licensed agents who specialize in this work. The Colorado Bar Association’s real estate law section can provide attorney referrals for more complex or commercial matters.
If You Lose at the BAA
If the BAA rules against you, Colorado law provides for further appeal under C.R.S. § 39-8-108.5 — to district court or the Colorado Court of Appeals. Be clear-eyed about this: court appeals of property tax valuations are expensive, slow, and pursued by virtually no Denver residential property owners. Litigation costs routinely exceed the potential tax savings on any single-family home or condo. If the BAA denies your petition, most Denver homeowners accept the result for that tax year and position themselves better for the next reassessment cycle. That’s the realistic outcome to plan for.
You may have heard that property tax increases in Colorado are “capped anyway” following Senate Bill 23-108, the emergency legislation passed in 2023 to reduce the impact of the reassessment cycle on taxpayers. That relief is real. But it applies on top of your assessed value, not instead of it. If your assessed value is wrong, the cap doesn’t fix it; it merely softens the damage. The correct assessed value still matters for future cycles, for refinancing and mortgage purposes, and because legislative relief mechanisms aren’t guaranteed to continue indefinitely. For Denver homeowners who qualify, our home & property coverage also explains other tax-reduction tools worth knowing, including senior exemption programs and appeal strategy across reassessment cycles.
Before You File
Work through this before you submit anything to the BAA.
Locate the mailing date printed on your denial notice. Count forward 30 calendar days. Write the date down and treat it as firm — no extensions exist.
Read your denial letter for strategic clues. The language the assessor used to deny your protest tells you what argument they found unpersuasive and what the BAA will expect you to address.
Assemble your evidence before you complete the petition form. The petition requires you to identify your grounds and your evidence. File complete.
Decide on written review or in-person hearing based on your evidence, not your frustration level.
Confirm with the BAA whether remote video hearings are available for the current cycle.
If your property value and case complexity warrant professional representation, contact a practitioner before the deadline. They need time to evaluate your case.
Confirm current BAA filing procedures directly with the office at 1313 Sherman Street, Room 315, Denver, CO 80203 — particularly whether online filing is available for the current cycle.
If you have questions about your specific denial, the Denver Assessor’s Office can be reached at (720) 913-4162. They can clarify what valuation methodology was applied to your property and, in some cases, what evidence would have been responsive. In my experience covering these disputes, most people don’t make this call. They should.
The BAA exists because the legislature recognized that mass-appraisal methodology produces errors and that individual property owners deserve an independent forum to challenge them. The process works. But only if you meet the deadline.
