Delaware is one of the few states that does not have a constitutional or statutory requirement to periodically adjust property assessed values for real estate taxation; the last county-wide property tax reassessment in New Castle County occurred in 1983. The recent property reassessments across the state were mandated by a Chancery Court decision in 2020 and were aimed at addressing inequities in school funding stemming from the outdated property values. To address this, New Castle County engaged Tyler Technologies to conduct the mandated real property reassessment. To arrive at the tentative new assessed values, Tyler Technologies utilized a mass valuation statistical model. The new assessed values are based on the 100 percent current fair market value of a property as of July 1, 2024.
There were approximately 215,000 parcels on the property tax roll in New Castle County that Tyler Technologies valued. Of those, 92 percent were residential properties. Tyler presented the preliminary assessed values in mid-November 2024 and, for the first time in 41 years, all property types experienced an increase in assessed value – on average by about 353 percent across all property types.
Given the backlash from many residential homeowners, in August 2025 legislators in Dover implemented a bill that permitted a split tax rate which created lower tax rates for residential properties compared to non-residential and commercial properties. This tax split intentionally shifted a larger share of the real estate tax burden to commercial/non-residential properties.
The taxpayers were also allowed to challenge these tentative assessed values with the county through the Board of Assessment Review. According to the county assessment department, they received approximately 5,300 appeal filings in 2025 and an additional 1,900 in 2026. To date, 1,700 of the 2025 property tax assessment appeals remain a year plus after the start of the filing. Of the total remaining, approximately 400 of those appeals involve commercial properties.
Obviously, the reassessment process was a monumental and onerous task given it had been 40+ years since the last mass assessment reevaluation. With 2025 filed appeals still in progress, an additional wave of appeals in 2026 – and likely more to follow in 2027 – the county has hired more assessors and started using AI models to work through the backlog. Needless to say, the outcome of the appeals process will reshuffle the entire tax roll once again.
Apex Realty Advisory’s office is located in Wilmington, and we cover the entire state of Delaware as well as the bordering areas of Maryland and Pennsylvania. We closely track local market conditions as well as sales and leasing activity. We have a team of qualified, independent, fee appraisers who hold state-certified general real property licenses and prestigious professional designations including the MAI and CRE®. Being local, we have a very good understanding of market dynamics, and we can efficiently solve a variety of real estate consulting and valuation engagements. If you find yourself in need of assistance, feel free to contact us by phone or through our website portal.