Oklahoma County modernises property assessments
Learn how Oklahoma County achieved industry-leading appeal rates and saved time and money by modernising property assessments at scale.
Oklahoma County Results
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The challenge
Meeting modern demands at scale with accuracy
As the state’s largest county, Oklahoma County sets the standard. But accelerating community growth made it impossible to maintain that standard without modernization.
In accordance with Oklahoma law, the assessors office is mandated to conduct a visual inspection of all taxable property at least once every four years to ensure accurate and equitable assessments. Traditionally, data collection was a cumbersome process, including manual information input.
“Back in the day, we just had stacks of aerial photos that were years old and not up to date. We had to do better,” said Oklahoma County’s Field Supervisor, Steve Stout.
It came with the operational expense of time, cost, safety, and reliability.
- Time: The county was sorting through physical stacks of paper maps
- Cost: Sending assessors on-site to walk parcels individually increased expenses
- Safety: Field staff face potential conflict with property owners.
- Reliability: Making decisions that impact constituents based on quick inspection
The right team was in place, but they were missing an imagery provider capable of supplying accurate, up-to-date aerials.
“Previously the delivery of our aerial images took nearly a year to create a final mosaic. By the time it was online, it was pretty much out of date. The process was convoluted due to each county wanting different outputs.”
Mike Morrison, Chief Deputy, Oklahoma County Assessor’s Office
The solution
Property intelligence for digital assessments
Property assessors run on accurate data. In 2017, Tim Conner, the GIS Director at Oklahoma County, ran into Nearmap at the Esri User Conference. This was the catalyst for the Assessor’s office changing its strategy.
Larry Stein was Chief Deputy for the Assessor at that time and both he and Tim were convinced that Nearmap would be a more reliable data source and become a benchmark on how to integrate technology to reduce assessment work for county offices.
Nearmap high-resolution imagery is captured with a ground sampling distance resolution of 4.4–7cm captured and processed per pixel and is refreshed up to 3 times per year.
With more than 330,000 property parcels across 720 square miles, the county’s small staff performs more than 90,000 appraisals every year. Using this high-resolution imagery, they can find new or improved residential and commercial properties to ensure accurate and equitable assessments.
When new Nearmap data is available, the internal and external field maps assessors use are updated automatically — allowing the team and constituents to identify changes across parcels with more ease, clarity, and historical reference data. When in the field, Oklahoma County’s team can operate with tablets to continuously update areas with additional details that in-office teams can also use.
With both the Assessor’s office and constituents using the same data, Oklahoma County started to watch its appeals decline and its reliability in data increase.
“We’re valuing residential and commercial properties, we’re valuing agricultural properties — and there are 160-acre tracts where access is impossible, but we can measure a barn that’s a mile from the street using Nearmap images. Having aerial imagery where you can zoom in and view it from every direction and from oblique angles, the tools on Nearmap create a virtual visit with precise dimensions.”
Steve Stout, Field Supervisor, Oklahoma County Assessor’s Office
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The impact
Better data, better value
The Assessor’s Office of Larry Stein is setting the benchmark by leveraging aerial imagery as the foundation for how it tracks and improves the community for locals across the county.
Reduced expenses passed down to taxpayers
By upgrading to a proactive aerial capture program, the county was able to reduce staff expenses. This saved the taxpayers approximately $5 million a year.
Industry leading accuracy in valuations
Fewer than 1% of property assessments are appealed annually – far below the 20% industry standard – saving time and reinforcing public trust in assessment practices.
Fewer site visits, more accurate decisions
Multiple updates per year ensure assessors always work from the most current, high-resolution imagery — eliminating guesswork and site visits.
Increased public confidence
Residents and property owners can independently verify assessments through public-facing tools, improving transparency.
Property intelligence trusted by governments
Multiply your time and extend budget value with geospatial data and aerial imagery in ways satellite images can’t.
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About Oklahoma County
Oklahoma County is the state’s most populous county, spanning roughly 720 square miles and more than 325,000 parcels. Larry Stein’s Oklahoma County Assessor’s Office is responsible for valuing every parcel in the county.