Housing affordability varies across Illinois. While Chicago dominates rent burden conversations, many smaller counties present their own challenges. Census data reveals that the percentage of income spent on housing differs by location, income levels, and local market conditions. Understanding these patterns helps identify where demand for affordable housing is most acute. From urbanized areas to rural communities, the gap between incomes and housing costs shapes the state’s construction priorities. Builders evaluating markets should examine both alternative housing trends and space-efficient construction as potential responses to cost pressures.
Measuring Housing Cost Burden in Illinois Counties
The U.S. Census Bureau tracks how much households spend on rent and utilities relative to their income. The standard benchmark for affordability is the 30% threshold: households spending more than 30% of income on housing are considered cost-burdened. Those spending more than 50% are severely cost-burdened. Across Illinois, the median percentage of income spent on housing ranges from under 16% in the most affordable counties to over 30% in the tightest markets.
Key Metrics for Comparison
When analyzing county-level data, three metrics provide the clearest picture of housing affordability:
- Median percent of income spent on housing: The midpoint value that splits households into those spending above and below that percentage
- Percent of households spending under 20% of income on housing: Indicates how many households enjoy comfortable affordability
- Percent of households spending over 30% of income on housing: Captures the share of cost-burdened renters who may struggle with other expenses
The National Context for Rent Burdens
Nationally, renters occupied 43 million housing units as of 2020. In 2019, renting was more affordable than buying in 59% of U.S. counties. By 2021, the dynamic flipped: owning became more affordable than renting in 63% of counties. This shift reflects rising rents alongside low mortgage rates during that period. For builders tracking these trends, housing starts, permits, and completions data provides essential context for where demand is growing fastest.
Counties with the Lowest Housing Cost Burdens
Several Illinois counties show median housing cost percentages below 16%. These counties share characteristics: lower population density, incomes that align reasonably with rents, and higher homeownership rates.
Monroe County Profile
Monroe County ranks as one of the most affordable in the state. With a median income of $85,747 and median monthly housing costs of $1,135, households spend 15.9% of income on housing. Only 22.3% exceed the 30% cost-burden threshold, while 57% spend under 20%. The county has 13,586 occupied households. This pattern of affordability in counties adjacent to metropolitan areas shows how rapid housing development strategies can help maintain balance between supply and demand.
Douglas County Affordability Factors
Douglas County presents a different picture. The median household income is $56,714 and median monthly housing cost is $751. The median percentage of income spent on housing is also 15.9%, but 23.9% of households exceed the 30% threshold, slightly higher than Monroe County. The lower income level is offset by proportionally lower housing costs. This balance reflects a market where housing supply has kept pace with demand more effectively than in many parts of the state.
| County | Median Income | Median Housing Cost | Median % on Housing | % Over 30% Threshold |
|---|---|---|---|---|
| Monroe | $85,747 | $1,135 | 15.9% | 22.3% |
| Douglas | $56,714 | $751 | 15.9% | 23.9% |
| Bureau | $57,436 | $761 | 15.9% | 20.5% |
| Saline | $44,090 | $585 | 15.9% | 21.1% |
| Pulaski | $34,640 | $462 | 16.0% | 21.0% |
The Connection Between Income and Housing Cost
One of the most revealing patterns in the Illinois housing data is how median income and median housing costs interact. In counties with higher incomes, housing costs rise proportionally, keeping the percentage stable. In counties with very low incomes, even modest housing costs can consume a large share of a paycheck.
Low-Income Counties Face Disproportionate Burdens
Pulaski County illustrates this dynamic. With a median income of $34,640 and median monthly housing costs of $462, the median percentage spent on housing is 16%. But the combination of very low incomes and limited housing options means over 21% of households still exceed the 30% threshold. Saline County has a median income of $44,090 and monthly costs of $585, with 21.1% of households cost-burdened. The roughly $10,000 annual income difference between these counties does not translate into better affordability outcomes because housing costs adjust to local markets. Builders looking at these markets should understand that housing recovery patterns often reach higher-income counties first before extending to lower-income areas.
The Affordability Gap in Rural Counties
Rural counties face unique challenges. Bureau County, with a median income of $57,436 and monthly costs of $761, shows 20.5% cost-burdened. While better than many urban areas, limited rental inventory in rural counties means prices can rise quickly relative to local wages when units become available. Without new supply entering the market, existing units age and rents drift upward, increasing the burden on renters even in nominally affordable counties.
Policy Implications for Housing Development
Counties with the lowest cost burdens are not necessarily the ones with the highest incomes. They are the ones where housing supply kept pace with demand. Monroe County ($85,747 median income) and Saline County ($44,090) both show median housing cost percentages near 16%. In both cases, the local market provides options matching what residents can afford.
Supply Constraints Drive Cost Increases
Counties that limit new development through zoning restrictions, high impact fees, or slow permitting processes see housing costs rise faster than incomes. Builders entering these markets face higher land costs and longer timelines that translate into higher rents for new units. A widening gap emerges between existing resident payments and new construction costs. Addressing these constraints requires understanding how presidential housing policy positions affect home builders and the broader housing market, from federal funding for infrastructure to tax incentives for affordable housing development.
Strategies for Reducing Cost Burden
- Streamlining permitting to reduce carrying costs for developers
- Allowing accessory dwelling units and smaller lot sizes to increase density without large infrastructure costs
- Targeting infrastructure investment to areas where housing construction is already viable but constrained by road, water, or sewer capacity
- Offering density bonuses or fee reductions for projects including affordable units for households below area median income
Comparing Illinois to National Trends
Illinois mirrors national patterns. Census data showing 43 million renter households nationwide reflects a long-term shift toward renting. The 2019-to-2021 flip from renting to owning being cheaper in most counties shows how volatile housing affordability can be over short periods. Illinois counties range from very affordable to severely burdened, a spread that reflects the state’s economic diversity.
What the Data Means for Builders
For residential construction professionals, the county-level data identifies where demand for affordable rental housing is highest and where new construction faces the most favorable conditions. Counties with high percentages of cost-burdened households and growing populations represent opportunities for housing development. Counties with low cost burdens but aging stock may offer renovation and infill opportunities. Tracking these local conditions is essential, particularly as national housing policy proposals continue to shape incentives for new development across different types of communities.
For builders and developers, the housing data from Illinois counties reveals a clear pattern: markets with median housing cost percentages below 17% tend to have either higher household incomes or lower median rents, sometimes both. Counties like Pulaski with very low incomes and correspondingly low rents present a different opportunity from counties like Monroe where incomes are high and the market serves them well. Each type of market requires a different approach to housing development.
Identifying Underserved Segments
In higher-income counties, the underserved segment is often middle-income renters earning 60% to 80% of the area median income. These households earn too much to qualify for most subsidized housing but not enough to comfortably afford market-rate units in the priciest developments. In lower-income counties, the underserved segment spans a wider range, from very low-income renters needing deep subsidies to moderate-income households who could benefit from well-designed, efficiently built units that keep rents below market norms. Understanding these segments requires reading county-level data alongside local employment trends and commuting patterns.
Land Costs and Feasibility
Land acquisition costs vary across Illinois. In rural counties like Bureau and Saline, land is cheaper but the rental market is thinner, requiring smaller projects and tighter cost control. In suburban counties like Monroe, land costs are higher but demand is stronger, supporting larger developments with more amenities. The feasibility calculation must account for both sides. A project that pencils out on paper in a low-cost county may fail if the local rental market cannot absorb the units quickly enough to cover debt service during the lease-up period.
Building Affordable Housing in Illinois Markets
For builders considering projects in counties with high housing cost burdens, several approaches have proven effective. Micro-apartments and co-housing reduce per-unit costs while maintaining livable spaces. Mixed-income developments spread risk across market segments and qualify for more financing programs. Energy-efficient construction reduces utility costs for tenants, improving effective affordability beyond the base rent.
Matching Product Type to Market Conditions
The right housing product varies by county. In higher-income areas like Monroe, the need is workforce housing: units affordable to teachers, nurses, and retail workers who earn less than the median. In lower-income counties like Pulaski or Saline, the need is for basic affordable units that can operate at rents sustainable for households earning $35,000 to $45,000 per year. Developers who match product type to local income profiles achieve better lease-up rates and lower turnover. Affordable housing design strategies including micro-apartments and co-housing offer flexible templates that can be adapted to different county-level conditions.
In higher-income counties, the underserved segment is often middle-income renters earning 60% to 80% of the area median income. These households earn too much for subsidized housing but not enough for market-rate units in the priciest developments. In lower-income counties, the underserved segment spans from very low-income renters needing subsidies to moderate-income households who benefit from efficiently built units. Understanding these segments requires reading county-level data alongside local employment trends.
Land acquisition costs vary across Illinois. In rural counties like Bureau and Saline, land is cheaper but the rental market is thinner, requiring smaller projects and tighter cost control. In suburban counties like Monroe, land costs are higher but demand is stronger, supporting larger developments. A project that pencils out in a low-cost county may fail if the local market cannot absorb units quickly enough to cover debt service during lease-up.
Financing Options for Affordable Development
Developers in Illinois counties can access several funding sources designed for affordable housing. The Illinois Housing Development Authority offers tax credits and gap financing. Local housing authorities may provide land at below-market rates. Community block grants from HUD can fund infrastructure improvements that support new housing. The key is assembling a capital stack that combines these sources with conventional debt and equity to make projects feasible where rents are constrained by what local households can pay.