Did your Boulder Notice of Valuation come in higher than you expected? You are not alone, and you do have options. With the right comps, clear documentation, and a simple plan, you can make a strong case to adjust your value. This guide walks you through Boulder County’s deadlines, the evidence that works, and each step of the appeal process so you can move forward with confidence. Let’s dive in.
Key Boulder deadlines
- Notices of Valuation are mailed on or before May 1. You can file your Assessor-level protest from May 1 through June 9. Mailed protests must be postmarked by June 9, and in-person filings are accepted until 5 p.m. June 9. Check the official appeal calendar for details on how to file through the county portal, mail, fax, or in person. See Boulder County’s appeals calendar.
- The Assessor issues a Notice of Determination by Aug. 15. If you disagree, you may appeal to the County Board of Equalization by Sept. 15. BOE hearings are held remotely and require advance evidence upload. Review BOE rules and scheduling.
- Colorado values property as it exists on January 1 of the tax year, and assessors use sales from a defined study period. This means very recent sales might be excluded if they fall outside the study window. Learn more about assessment timing and terms from the state’s property tax resources: Property tax terminology and the ARL on assessment operations.
How values are set in Colorado
- Assessors consider three valuation approaches where applicable: sales comparison, cost, and income. For most residential property, the sales comparison approach carries the most weight. See the state’s guidance on valuation methods in the Assessors’ Reference Library: valuation procedures.
- The sales study period defines which closed sales can be used as comparables. Counties follow a statutory look-back window, often 18 to 60 months depending on the cycle and property type. Confirm the study period for your year so your comps align with what the Assessor is required to use. State terminology overview.
Build strong evidence
Comparable sales that fit the study window
- Pull 3 to 6 closed sales that closely match your home’s location, lot size, square footage, age, and condition, and that fall inside the county’s study period. Explain any adjustments for bedrooms, bathrooms, garages, finished basements, or views. The sales comparison approach is central for residential appeals. ARL valuation procedures.
- For market context while you compile comps, review current Boulder snapshots and trends. Use them to understand pricing, then anchor your appeal to sales within the study window. See Boulder market snapshots.
Photos, repairs, and documentation
- Include clear, dated photos that show condition on or before the assessment date. Foundation movement, roof damage, outdated systems, or deferred maintenance can affect market value. Add contractor estimates or bids to help quantify impact.
- If you bought or sold recently, attach your Closing Disclosure and note any unusual conditions like related-party transactions or significant concessions.
Independent appraisal when stakes are high
- A USPAP-compliant appraisal prepared near the valuation date can be persuasive, especially if it explains material differences the Assessor missed. This can be worth it for larger value disputes. ARL valuation procedures.
Income properties
- For rentals or multiunit assets, provide rent rolls, leases, income and expense statements, and vacancy data for the period around the valuation date. The income approach is relevant for income-producing property. ARL valuation procedures.
New builds and partial completion
- Show the percentage of completion as of January 1 with photos, permits, and invoices. Colorado requires valuation based on physical condition as of that date. ARL assessment operations.
BOE evidence submission rules
- If you move beyond the Assessor to the BOE, upload your evidence as PDFs at least three business days before your hearing. You can upload only five documents, so combine and label files clearly. Evidence submitted to the Assessor is not automatically included at the BOE, so resubmit what you want considered. BOE instructions and upload portal.
Step-by-step appeal
Stage 1: Protest with the Assessor
- File your initial protest by June 9 through the Boulder County system. Keep your package concise: a one-page summary, your best 3 to 6 comps, photos, and any estimates. The Assessor will review and issue a Notice of Determination by Aug. 15. Appeals calendar and filing methods.
Stage 2: Appeal to the BOE
- If you disagree with the Assessor’s decision, file with the BOE by Sept. 15. Hearings are remote on Microsoft Teams. Upload your final evidence early, stay within the five-document limit, and be ready to present succinctly. The BOE can affirm, reduce, or increase your value. BOE process and rules.
Stage 3: Further appeals
- After the BOE decision, you may appeal to the Colorado State Board of Assessment Appeals, to district court, or to binding arbitration. Deadlines apply, and the process becomes more technical. Consider professional help at this stage. BOE guidance.
Outcomes and realistic expectations
- Many protests result in modest adjustments or denials. Success depends on strong, study-period comps and clear condition evidence. Some recent reporting across the metro area noted high denial rates during recent cycles. See reported trend context.
- Appeals can increase value if the Assessor presents stronger evidence. The BOE warns about this risk, so weigh next steps carefully. BOE information.
Timeline checklist
- Early May: Open your Notice of Valuation immediately. Confirm property characteristics and start pulling comps within the county’s study window. Take dated photos of current condition. Appeals calendar.
- By June 9: File your protest with the Assessor. If mailing, use a method that confirms postmark by June 9.
- By Aug. 15: Review the Notice of Determination. If needed, prepare your BOE filing.
- By Sept. 15: File with the BOE and upload your PDF evidence at least three business days before your hearing. Arrange a representative if you cannot attend.
When to get help
- If the value difference is small, a homeowner-prepared packet of solid comps and photos often works. For larger gaps, complex properties, or income-producing assets, a licensed appraiser or attorney can strengthen your case. Fees vary by scope and can range from several hundred to a few thousand dollars.
- Want a second set of eyes on your comps or a referral to trusted local appraisers and contractors? We are happy to help you prepare a clean, persuasive package.
Ready to appeal with confidence?
If you want help interpreting comps, reality-checking your strategy, or connecting with proven local pros, reach out. You will get clear guidance, practical next steps, and support that respects your time and budget. Start the conversation with The Greer Group.
FAQs
What are Boulder’s key appeal deadlines?
- Notices of Valuation arrive by May 1, Assessor protests are due by June 9, Notices of Determination are issued by Aug. 15, and BOE appeals are due by Sept. 15.
Which comps work best in a Boulder appeal?
- Closed sales that match location and property traits and fall inside the county’s sales study period, with clear adjustments and minimal differences.
Can my recent purchase price be used as evidence?
- Yes, if it was an arm’s-length sale and within the study period; include your Closing Disclosure and explain any unusual terms.
What if I cannot attend my BOE hearing?
- Hearings are usually not rescheduled; you can designate a representative with a letter of agency and must still upload evidence on time.
Could appealing raise my property value?
- It can; the BOE can affirm, reduce, or increase value if the Assessor’s evidence supports a higher figure, so weigh the risk before filing.
