Two signals point in different directions in 60540: Zillow’s current ZIP ZORI is $2,467 per month, up 6.04% from a year earlier, while the direct ZIP resale median discussed below is lower year over year. ZORI is a typical observed asking-rent index blended across rental types; it records market asking-rent conditions, not closed leases, household spending, or the rent of any specific address. The 60540 label is both a Zillow ZIP market identifier and a Census ZCTA match. A ZCTA is a statistical area and is not identical to a USPS delivery ZIP. That shared label allows parallel reading of the evidence but does not make their sampled populations, timing, or measurements interchangeable.
Longer ZORI history gives the rent signal context without making it predictive. Through the stated Zillow history endpoint, exact same-month change annualizes at 6.04% over one year, 5.08% over three years, and 6.42% over five years. Recent direction therefore confirms the positive longer path rather than breaking from it, although its pace exceeds the three-year rate and trails the five-year rate. The series contains 66 monthly observations with 100% coverage. Annualized monthly-return variability is 3.40%, which limits confidence in treating one current reading as a precise fixed rent. The deepest observed peak-to-trough decline was 3.99%, showing that the record has not moved in one direction only. Transparent national discovery ranks are 222 for momentum, 2,143 for stability, and 681 for balanced history among eligible ZIPs, where lower ranks are higher. These are backward-looking measurements, not forecasts or investment recommendations.
ZORI should not be substituted for the ACS rent measure. The matched Census ZCTA ACS 2024 five-year survey reports a $1,980 median gross rent, with a $147 margin of error; it is a survey of occupied renter homes and includes selected utilities. This median is 24.6% below the current asking-rent index, a difference that cannot be read as a direct quote-to-lease spread because the measures have distinct populations, utility treatment, and observation periods. The citywide Zillow asking-rent context for Naperville is $2,310, the countywide Zillow asking-rent context for DuPage County is $2,140, and the metro-wide Zillow asking-rent context for Chicago-Naperville-Elgin, IL-IN-WI is $2,275. Those city, county, and metro figures are wider context only; none replaces the direct ZIP asking-rent index or the matched-ZCTA survey.
Bedroom sizing requires another boundary. FY 2026 HUD FMR/SAFMR is an administrative, bedroom-specific standard, not asking rent, and its local ladder is used here only to scale the ZIP ZORI. That method produces modelled monthly ZIP estimates of $2,051 for a studio, $2,186 for one bedroom, $2,467 for two bedrooms, $3,175 for three bedrooms, and $3,674 for four bedrooms. These are modelled estimates rather than measured bedroom rents: they preserve the local HUD ladder’s relative steps around the ZIP index instead of reporting observed listings, leases, or tenant payments. The equality between the two-bedroom model and ZORI is an anchor of the method, not a measurement of a typical two-bedroom transaction. HUD therefore supplies a sizing framework, while Zillow supplies the underlying all-type asking-rent index.
The income and burden evidence adds a distinct household screen. At 30% of income, sustaining the current monthly ZORI for a year produces a required-income screen of $98,680. This is arithmetic, not advice and not an applicant qualification rule. Against the ZCTA ACS median household income of $157,102, annualized ZORI equals 18.8% of the median; total-household income is nevertheless not renter income and cannot describe any applicant. In the ACS renter sample, 1,462 of 3,707 renter households, or 39.4%, reported gross-rent burden at or above the separate 30% burden threshold. Because this is a five-year survey result on occupied homes, including its gross-rent utility treatment, it cannot establish the affordability or burden of a particular available unit. The aggregate income comparison and renter burden measure answer different questions, so neither overrides the other.
Stock and vacancy describe the ZCTA housing base rather than a live rental availability feed. The ACS estimates 16,198 housing units, including 12,709 single-family units and 1,272 units classified as large multifamily. It also counts 1,037 vacant units, an overall vacancy rate of 6.4%. These totals help place the renter survey and asking-rent index in a housing-stock setting, but they do not identify the tenure, condition, price point, or lease readiness of any particular vacant home. A vacancy count cannot prove that a suitable unit is currently offered, nor can it establish a likely concession, tenant outcome, or rent for a specific property. The survey-based stock mix should likewise not be converted into a current listing mix.
The resale cross-check is mixed and must remain in its own transaction universe. Redfin’s direct rolling-three-month ZIP observation reports a $689,844 median sold price, down 3.52% year over year; it also records 141 homes sold and a median 41 days on market. Inventory stood at 145 homes and 3.1 months of supply. Sale-to-list signals were firm in the same resale observation, with an average sale-to-list ratio of 100.61% and 46.76% of sales above list. This is for-sale evidence, not rental transactions, rental comparables, or property economics. The annualized ZIP ZORI divided by the median sold price is 4.29%, only a cross-source screening ratio. The sale-price decline challenges a simple confirmation of the rent and history strength, whereas the sale-to-list signals show that the resale evidence is not uniformly soft; neither result validates the household affordability screen or describes identical properties.
Several limits govern any property-level use of these data. The packet contains an index, a ZCTA survey, administrative HUD standards, and aggregate resale observations, each with different timing and coverage; none gives unit-specific leases, utility allocations, operating costs, or listing-level condition. A concrete review should verify the exact address and its delivery ZIP, advertised asking rent, bedroom count, lease start date, tenant-paid versus included utilities, concessions, and current availability. If sale evidence is considered, it should be kept separate from rent evidence and checked for the relevant property type, sale date, and transaction status. Those checks can test whether a listing aligns with the source definitions, but they cannot turn the modelled ladder, vacancy count, or screening ratio into a measured unit result. Does a specific address’s advertised rent and lease structure actually match the data universe being used?