# Understanding the Affordable Requirements Ordinance (ARO) rules for rental housing Chicago City Council adopted "ARO 2021", a revision to the 15-year old ordinance that requires owners of properties that trigger the rules to provide a portion of dwelling units at affordable prices to income-eligible households. The new rules are both more complex and more flexible, and create rulesets based on five geographies across Chicago. The matrix below – for proposed rental projects – has one row for each geography while the columns describe the geography's rules for each rule standard. Another article, [[Zoning Assessment|How to read zoning assessments]], describes how to determine the ARO geography for a particular address or PIN. ## ARO matrix (for rental housing only) <table class="table table-condensed table-striped table-hover small"> <tbody> <tr> <th>Standard &rarr; <br />Area name &darr;</td> <th>Set aside (baseline, may be different if adhering to different rules)^[1]</td> <th>Affordability</td> <th>Set aside in 30+ unit buildings</td> <th>On-site requirement (of the set aside units)</td> <th>+ On/Off site requirement (in addition to On-site requirement)^[3]</td> <th>Off-site unit standards^[3]</td> <th>Remaining units</td> </tr> <tr> <td>Low-Moderate</td> <td>10%</td> <td>60% AMI weighted average^[5]</td> <td>N/A</td> <td>?</td> <td>?</td> <td>Off-site units can be existing or new but must be in a Community Preservation, Inclusionary, or Downtown area.&nbsp;</td> <td>?</td> </tr> <tr> <td>Community Preservation</td> <td>20%</td> <td>60% AMI weighted average (see option 1 for minimum weighting requirements)</td> <td>Can be lower than 20% if deeper affordability is provided (see options 1A, 2, 3, and 4)</td> <td>25%</td> <td>25%</td> <td>Off-site units can be existing or new construction but must be in a Community Preservation areas (<a href="https://www.chicago.gov/content/dam/city/depts/doh/aro/ARO%20Rules_Oct_2021.pdf" target="_blank" title="ARO rules (PDF)">Rule 6.2.3.1</a>). Off-site units must be within 1 mile of the triggering project. MCC 2-44-085(H)(1)</td> <td>Remaining 50% of set aside units can be on-site, off-site, or paid for by an in lieu fee.&nbsp;</td> </tr> <tr> <td>Inclusionary</td> <td>20%</td> <td>60% AMI weighted average^[5] (see option 1 for minimum weighting requirements)</td> <td>Can be lower than 20% if deeper affordability is provided (see options 1A, 2, 3, and 4)</td> <td>25%</td> <td>25%</td> <td>Off-site units must be new construction in Community Preservation areas (<a href="https://www.chicago.gov/content/dam/city/depts/doh/aro/ARO%20Rules_Oct_2021.pdf" target="_blank" title="ARO rules (PDF)">Rule 6.2.3.1</a>). Off-site units can be existing or new construction in Inclusionary and Downtown areas.</td> <td>Remaining 50% of set aside units can be on-site, off-site, or paid for by an in lieu fee.&nbsp;</td> </tr> <tr> <td>Downtown</td> <td>20%</td> <td>60% AMI weighted average^[5] (see option 1 for minimum weighting requirements)</td> <td>Can be lower than 20% if deeper affordability is provided (see options 1A, 2, 3, and 4)</td> <td>25%</td> <td>25%</td> <td>Off-site units can be existing or new but must be in a Community Preservation, Inclusionary, or Downtown area.</td> <td>Remaining 50% of set aside units can be on-site, off-site, or paid for by an in lieu fee.&nbsp;</td> </tr> <tr> <td>Little Village & Pilsen ^[2]ARO 2015</td> <td>20%</td> <td>60% AMI</td> <td>N/A</td> <td>50%</td> <td>No off-site option; options are additional on-site or in lieu fee</td> <td>No off-site option</td> <td>In lieu fee option^[4]</td> </tr> </tbody> </table> <h2>Weighting options</h2> The table below shows the weighting options; from the [Municipal Code of Chicago 2-44-085-F-2](https://codelibrary.amlegal.com/codes/chicago/latest/chicago_il/0-0-0-2693409). Note that Option 1 requires a fraction of the units to be rented to households earning less than 60% AMI. *Screenshot of a table showing the weighting options; from the Municipal Code of Chicago 2-44-085(F)(2)* ## Footnotes <p>^[1] Set aside can be reduced if the number of units with more bedrooms is increased.</p> <p>^[2] The Little Village and Pilsen Pilot Areas expired at the end of 2023. At that time, the Pilsen part largely converted to a Community Preservation area and the Little Village part largely converted to a Low-Moderate area. These pilot areas have additional standards in Municipal Code of Chicago (MCC) 2-44-105.</p> <p>^[3] Off-site units have additional standards that are not listed here. <a href="https://www.chicago.gov/content/dam/city/depts/doh/aro/ARO%20Rules_Oct_2021.pdf" target="_blank" title="ARO rules (PDF)">See section 6.2.3 in the DOH ARO rules</a>. Special notes: If the triggering project is located in a transit-served location (TSL, but also known as TOD), each off-site unit must also be located in a substantially comparable transit-served location (use Property Finder to find properties in TSLs); each off-site unit must have at least two bedrooms.</p> <p>^[4] If the project receives TIF funding, 100% of set aside units must be on-site.</p> <p>^[5] "...at a weighted average of 60% of the AMI, provided the maximum income level for any affordable unit in a rental project may not exceed 80% of the AMI." 2-44-085(F)(1)</p> ## Additional notes The ARO ordinance requires that all on-site units are accessible units. The ARO rules specify that developers must give preference in leasing accessible units to people with disabilities. ARO rules specify that developers must give preference in leasing multi-bedroom units to multi-person households. # Related articles - See the [[Zoning Assessment#Fair Market Rent]] article - [[Chicago Housing Authority]] - [[Affordable housing data]] - [Blog post from September 2021](https://www.chicagocityscape.com/blog/cityscape-has-the-maps-you-need-to-locate-where-new-aro-rules-apply-c5376e9523) about the new ARO requirements and map