80503 Property Tax Rate
Longmont, Colorado · Part of Boulder County
Effective Tax Rate
0.55%
104.1% above state avgMedian Annual Tax
$3,841
$320/mo escrow
Estimate Your Tax
Annual Tax
$3,841
Monthly
$320
Eff. Rate
0.55%
Buyer decision brief
What ZIP 80503 means for your housing budget
Use this ZIP page to compare recurring tax burden before you compare listing prices. The numbers below are Census ZCTA estimates, so they are strongest for neighborhood comparison and weakest for parcel-specific tax planning.
Monthly escrow signal
$320/mo
Based on median annual tax paid
State context
0.13 percentage points above the Colorado average
Colorado average: 0.42%
Data confidence
High confidenceThe Census margin of error is $124, about 3% of the median tax estimate.
Verify before you offer
- Confirm parcel assessed value with Boulder County assessor.
- Check homestead, senior, veteran, and disability exemptions.
- Ask whether purchase triggers reassessment or value-cap reset.
- Review school district and special assessment boundaries.
Lower-rate similar ZIPs
This is informational content, not tax, legal, or mortgage advice. Local assessor records remain the source of truth for a specific property.
Data confidence ledger
Can you trust ZIP 80503 for comparison?
ACS vintage
2019-2023 ACS 5-Year Estimates
Five-year Census ZCTA estimates.
ZCTA caveat
Census area, not parcel boundary
USPS ZIP routes and taxing districts can differ inside the same area.
Field completeness
3/3 required fields
Median tax, home value, and derived rate are present.
MOE status
Strong ACS confidence
$124 tax MOE, 3% of the median tax estimate.
Last site refresh
March 10, 2026
Dataset and page-quality audit run locally before publication.
County fallback
County advisory available
Boulder County is used for assessor verification and broader context.
Tax bill anatomy
What can change your actual bill in ZIP 80503
Use the ZIP estimate to compare neighborhoods, then verify these parcel-level inputs before relying on a payment estimate.
Assessed value
The ZCTA median home value is $704,800, but your bill starts with the local assessed value for a specific parcel.
Effective rate
The displayed rate is 0.55%, derived from median tax paid divided by median home value.
Exemptions
Homestead, senior, veteran, disability, and local exemptions can reduce taxable value. Confirm eligibility before estimating escrow.
Reassessment
A purchase can change assessed value depending on Colorado and county rules. Ask how sale price affects the next assessment cycle.
Escrow impact
The median tax paid in this ZCTA equals about $320 per month before insurance, HOA dues, or special assessments.
Assessor verification
Boulder County assessor or tax collector records are the source of truth for parcel taxes, appeal windows, and exemptions.
How ZIP 80503 Compares
Median Annual Property Tax
ZIP 80503
0.55%
Effective rate
Colorado Avg
0.42%
Effective rate
National Avg
1.10%
Effective rate
State Ranking
Property Tax Rank in Colorado
Higher than 87% of ZIP codes in Colorado(87th percentile, 454 ZIPs compared)
Property Tax Analysis
Property Tax Insights for ZIP 80503
Property owners in ZIP code 80503 (Longmont, Colorado) pay a median of $3,841/year in property taxes on homes valued at $704,800. This translates to an effective tax rate of 0.55%, which is 31% above the Colorado state average of 0.42%.
The monthly property tax burden for a median-valued home in 80503 is approximately $320, which factors into escrow payments on mortgages. This ZIP code is located within Boulder County. This is $1,959 more than the Colorado average of $1,882/year.
Compared to similar ZIP codes in Colorado, 80503 has higher property taxes. ZIP codes with similar effective rates include 80654 (0.55%) and 80528 (0.54%).
In Longmont, property taxes represent approximately 3.2% of the median household income of $118,465, providing context for the relative tax burden on homeowners in this area.
Colorado's Gallagher Amendment was repealed in 2020, eliminating statewide assessment caps; your property will reassess to current market value at sale, and mill levy growth is limited by TABOR. Boulder County offers a Senior Homestead Exemption for owners 65 or older who have resided in the home for 10+ years — apply through the Boulder County Assessor to reduce assessed value. File your exemption application with the Boulder County Assessor before April 15 of the year following your purchase if you meet age and residency requirements.
Frequently Asked Questions
What is the property tax rate in ZIP code 80503?
How much are property taxes in Longmont, CO (80503)?
How does ZIP 80503 compare to the Colorado average?
What is the median home value in ZIP 80503?
What county is ZIP code 80503 in?
Margin of Error
The median property tax estimate for this ZIP code has a margin of error of ±$124. ZCTA-level data has wider margins than county-level estimates due to smaller sample sizes.
County-Level Data
ZIP code 80503 is part of Boulder County, Colorado. View the full county profile for broader context and more data.
View Boulder County on TaxByCounty →Explore Longmont, CO
View all 3 ZIP codes in Longmont with property tax comparisons.
View Longmont Property Tax Rates →Why compare these ZIPs?
Better comparison set for ZIP 80503
Each ZIP highlights a homebuyer tradeoff: lower rate, stronger value context, shared county rules, city boundary changes, or nearby missing data.
80504
Longmont, CO
0.00 percentage points lower than ZIP 80503.
Rate
0.54%
Tax
$3,009
Quality
89
80501
Longmont, CO
0.03 percentage points lower than ZIP 80503.
Rate
0.52%
Tax
$2,387
Quality
96
80510
Allenspark, CO
0.17 percentage points lower than ZIP 80503.
Rate
0.38%
Tax
$2,913
Quality
74
80481
Ward, CO
0.10 percentage points lower than ZIP 80503.
Rate
0.44%
Tax
$2,447
Quality
84
80455
Jamestown, CO
0.09 percentage points lower than ZIP 80503.
Rate
0.46%
Tax
$2,462
Quality
84
80026
Lafayette, CO
0.07 percentage points lower than ZIP 80503.
Rate
0.48%
Tax
$3,155
Quality
89
80466
Nederland, CO
0.04 percentage points lower than ZIP 80503.
Rate
0.50%
Tax
$3,327
Quality
89
80305
Boulder, CO
0.04 percentage points lower than ZIP 80503.
Rate
0.51%
Tax
$4,980
Quality
101
Data from U.S. Census Bureau, American Community Survey 2019-2023 5-Year Estimates (ZCTA level). ZIP Code Tabulation Areas (ZCTAs) are Census approximations of USPS ZIP codes.
Estimates are informational only and should not be used as financial or legal advice.