Overview
Overlapping enrollments are one of the most critical data quality issues in HMIS. They occur when a client is enrolled in two or more projects at the same time in a way that suggests they were occupying multiple units or receiving housing services simultaneously. This article explains what overlapping enrollments are, why they matter for the Chicago CoC, HUD’s guidance for resolving them, and how agencies can use EVA to improve internal data quality.
Table of Contents
- What Are Overlapping Enrollments?
- Why Overlaps Matter
- Level 1: Entry/Exit-Based Residential Projects
- Level 2: Entry/Exit vs Night-by-Night
- Level 3: Residential vs Permanent Housing
- Level 4: Permanent Housing vs Permanent Housing
- Best Practices
- Using EVA for Data Quality
What Are Overlapping Enrollments?
Based on HUD HMIS Data Standards, overlapping enrollments happen when a client’s enrollment dates overlap across projects. This creates a situation that is logically and physically impossible unless specifically allowed by funding rules.
Example:
A client is enrolled in Rapid Re-Housing starting on 04/14/2025 and also enrolled in Permanent Supportive Housing from 10/01/2024 to 10/18/2025. This means the client appears to be active in two Permanent Housing projects at the same time, which is not allowed. HUD expects this overlap to be corrected by updating the RRH Exit Date so it occurs before the PSH Housing Move-In Date.
Why Overlaps Matter
Overlapping enrollments are more than a technical error, they represent a breakdown in accurate data collection and reporting. HUD considers these issues critical because they create scenarios that are not possible in real life and undermine the integrity of HMIS data.
Impact on Utilization and Inventory
When a client appears enrolled in two projects at the same time, HMIS counts them twice. This inflates bed utilization rates and makes it look like programs are serving more people than they actually are. For shelters, this can make occupancy appear over 100%, and for housing programs, it can misrepresent unit availability.
Impact on HUD Reporting
HUD reports such as the Point-in-Time (PIT) Count, Housing Inventory Count (HIC), Longitudinal System Analysis (LSA), and System Performance Measures (SPMs) rely on accurate enrollment dates. Overlaps cause:
- Incorrect counts of people experiencing homelessness.
- Misreported housing placements and retention rates.
- Errors in measures like Length of Stay and Returns to Homelessness.
Impact on Coordinated Entry
Overlaps make it appear that clients are in multiple programs simultaneously, which could disrupt coordinated entry prioritization.
Community Planning
Chicago CoC uses HMIS data to plan housing resources and evaluate program effectiveness. Overlaps undermine this process by creating false indicators of demand and utilization.
HUD Guidance and Hierarchy
Level 1: Entry/Exit-Based Residential Projects
Definition: Occurs when a client is enrolled in two or more residential projects that use Entry Date and Exit Date to indicate occupancy at the same time. These projects include Emergency Shelter (Entry/Exit method), Transitional Housing, and Safe Haven.
Why It Matters: These projects represent physical units where a client resides. Any overlap means the client is recorded as occupying two units simultaneously, which is logically and physically impossible. HUD considers these the most severe overlaps and expects them to be corrected immediately.
Example Scenario:
Client enrolled in Emergency Shelter A: 01/01/2025–01/10/2025
Client enrolled in Transitional Housing B: 01/05/2025–01/15/2025
Provider Steps:
-
Check HMIS Enrollment History
Open the client’s record and review all active and historical enrollments. Confirm which projects overlap and the exact dates. -
Verify Documentation
Look at the intake and discharge paperwork for your project. Confirm where the client was physically staying during the overlap. -
Determine Correct Dates
Identify which enrollment dates need adjustment based on actual stay. If your project’s dates are correct, contact the other agency. You can utilize the ATA Resource List. -
Update HMIS
Correct Entry and Exit Dates so they reflect actual occupancy. Remove duplicate enrollments if they were entered in error. -
Confirm No New Overlaps
After changes, review the client’s timeline to ensure no new overlaps were created.
HUD Expectation: 100% correction required.
Level 2: Entry/Exit vs Night-by-Night
Definition: Occurs when a client is enrolled in a residential project using Entry/Exit dates and is also recorded for bed nights in a Night-by-Night shelter during the same period.
Why It Matters: These overlaps are physically impossible because they imply the client was counted in two shelters on the same nights. HUD expects these to be corrected nearly 100% of the time.
Example Scenario:
Client enrolled in Emergency Shelter A (Entry/Exit): 01/01/2025–01/10/2025
Client recorded for bed nights in Emergency Shelter B (Night-by-Night): 01/05/2025, 01/06/2025, 01/07/2025
Provider Steps:
-
Review Both Records
Check the Entry/Exit enrollment and the bed night dates. Identify which nights overlap. -
Check Internal Notes
Confirm where the client stayed on those nights using shelter logs or case notes. -
Adjust Dates
If the client was at the Night-by-Night shelter, update the Exit Date for the Entry/Exit project so it ends before the bed nights. -
Re-Enroll if Needed
If the client returned later, create a new enrollment with the correct dates instead of extending the original one. -
Communicate if Unclear
If you’re unsure, reach out to the other agency to confirm dates before making changes. You can utilize the ATA Resource List. -
Confirm No New Overlaps
After changes, review the client’s timeline to ensure no new overlaps were created.
HUD Expectation: 100% correction required
Level 3: Residential vs Permanent Housing
Definition: Occurs when a client is enrolled in a residential project and is also recorded as occupying a Permanent Housing unit based on Housing Move-In Date.
Why It Matters: This is the most common overlap because clients often remain enrolled in shelter after moving into housing. HUD expects nearly all Level 3 overlaps to be corrected.
Example Scenario:
Client enrolled in Emergency Shelter: 02/01–02/10
Client has a Housing Move-In Date in Rapid Re-Housing on 02/05
Provider Steps:
-
Check Housing Move-In Date
Verify the date against lease or placement documentation. This date should reflect when the client physically moved into housing. -
Compare Shelter Exit Date
If the shelter enrollment extends beyond the move-in date, update the Exit Date so it ends before housing move in date of the Permanent Housing project. -
Confirm Timeline
Review the client’s entire enrollment history to ensure the sequence makes sense and no new overlaps exist. -
Determine Correct Dates
Identify which enrollment dates need adjustment based on actual stay. If your project’s dates are correct, contact the other agency. You can utilize the ATA Resource List. -
Confirm No New Overlaps
After changes, review the client’s timeline to ensure no new overlaps were created.
HUD Expectation: Correct 99% of overlaps. In rare cases, where you feel the overlap is legitimate, please reach out to Helpdesk@allchicago.org
Level 4: Permanent Housing vs Permanent Housing
Definition: Occurs when a client is enrolled in two Permanent Housing projects at the same time. These often happen during transfers between RRH and PSH or between two PSH units.
Why It Matters: These overlaps can make inventory appear duplicated and misrepresent housing utilization. HUD expects these overlaps to be corrected 99% of the time.
Example Scenario:
Client was housed in RRH on 03/05/2025 and later transferred to PSH on 04/05/2025 without RRH exit recorded.
Provider Steps:
-
Identify Transfer or Error
Determine if this is a legitimate transfer or a data entry mistake. -
Verify Documentation
Check lease start dates, transfer referral date in HMIS, or case notes to confirm when the client moved from one unit to another. -
Determine Correct Dates
Identify which enrollment dates need adjustment based on actual stay. If your project’s dates are correct, contact the other agency. You can utilize the ATA Resource List. -
Update Exit Dates
The first project should have an Exit Date before the second project’s Housing Move-In Date. -
Confirm No New Overlaps
After changes, review the client’s timeline to ensure no new overlaps were created.
HUD Expectation: Correct 99% of overlaps. In rare cases, where you feel the overlap is legitimate, please reach out to Helpdesk@allchicago.org
Best Practices
-
Keep Enrollment Dates Accurate
- Ensure that Entry Dates, Exit Dates, and Housing Move-In Dates reflect actual client activity. Accurate dates prevent situations where a client appears active in multiple projects at the same time.
-
Coordinate Across Programs
- If a client transfers to another program, make sure dates line up. A short conversation or email can prevent dual enrollments and save time later.
-
Use Available Tools
- EVA is great for spotting overlaps within your agency and checking Housing Move-In Dates. It can also be paired with HMIS reports for a full picture.
Using EVA for Data Quality
EVA is an ABT/HUD-developed tool that helps agencies review and correct data quality issues in HMIS. It uses a hashed CSV export from HMIS to generate reports highlighting common errors. Please find more details on EVA in our EVA Article.
What EVA Does:
- Identifies overlapping or duplicate enrollments within your agency’s projects.
- Flags incorrect or missing Housing Move-In Dates.
- Highlights Head of Household errors and Enrollment CoC mismatches.
- Provides dashboards and downloadable reports for easy review.
Important Limitation: EVA only detects overlaps within your agency. Cross-agency overlaps require manual review and provider-to-provider communication.
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