New listings are an inflow, while inventory reflects homes active during the month. Treating them as interchangeable can hide how quickly listings change status.
Chicago, Elmhurst, and Glen Ellyn each recorded more new listings in August 2026 than a year earlier. Inventory rose in the two suburbs but fell in Chicago.
That is not a contradiction. The measures answer different questions.
A flow is not a stock
New listings count homes entering the market. Inventory counts unique listings active at any time in the month. A home can appear in both measures and then move under contract or leave the market.
Without linked listing histories, the city series cannot show which status change caused the final inventory result. Dividing one measure by the other would not create a valid conversion rate.
A one-year increase can coexist with a longer-term shortage
Elmhurst inventory rose 23.1% from August 2025, and Glen Ellyn rose 18.3%. Both remained about 69% below August 2019.
The 2019 comparison does not say inventory should return to that level. It shows why a rebound from a low base and a return to an earlier count are different claims.
What a buyer or seller still needs
A buyer needs the number of current homes matching the actual search, along with status, price history, condition, and timing. A seller needs the direct active and pending competition for the property.
City inventory can frame the market conversation. It cannot identify the homes that matter to one decision.
Source and method: Zillow seasonally adjusted city inventory and new-listing series. The full three-city study discloses the complete-case sample, three excluded cities, exact values, and formulas.