SCI Mercer Population & Capacity: What the Numbers (and Custody Level) Mean
Seen different population numbers for SCI Mercer and wondered which one's right? You're not imagining things — the Pennsylvania DOC reports the same month's count several different ways. Here's how to read the figures so you know what you're actually looking at.
The Pennsylvania DOC's Monthly Population Report (as of December 31, 2025) lists Mercer (MER) with a total population of 1,379, a capacity of 1,476, and 93.4% occupancy. Scroll further into the same PDF and you'll find a "physically present" count of 1,361 - that's the on-site headcount. How do these numbers connect? The report breaks it down: 1,361 physically present, plus 3 in hospital and 15 on temporary absence, equals the 1,379 total in the summary table.
Note: These numbers seem conflicting until you notice the categories. The DOC's "total" (1,379) includes people not physically at the facility that day - hospital stays, temporary absences. The "physically present" count (1,361) is who's actually on site. When citing a number, note the DOC source and the "as of" date.
SCI Mercer's custody level changed on July 1, 2008, when it became a level 2–3 facility according to Pennsylvania DOC records.
Most "different numbers" come from report formatting, not actual disagreements about the count. The monthly report shows a facility's total population in the summary row, then breaks down how that total is built: physically present count plus outcounts like hospital and temporary absence. For Mercer, that's why you see 1,361 in one section and 1,379 in another - 1,361 is the on-site headcount, plus 3 (hospital) and 15 (temporary absence) gets you to 1,379. Comparing numbers across sources? Check the dates. The monthly report is tied to a specific "as of" date, while other DOC pages may update on different schedules.
- Pull the latest DOC Monthly Population Report PDF - note the “as of” date on the report so you know exactly what day the count represents.
- Read the Mercer (MER) summary row first - that’s where you’ll see the total population, capacity, and occupancy percentage.
- Reconcile “physically present” vs. “total” - use the report’s breakdown that shows physically present plus hospital and temporary absence (for example, 1,361 + 3 + 15 = 1,379).
- If you need a current, on-the-ground answer, call the facility - ask for the most up-to-date population context and whether anything operational is affecting normal routines.
Note: A population or occupancy percentage doesn’t automatically tell you what visits, phones, or day-to-day conditions will look like. If you’re making plans, confirm current policies directly with the facility.
- ✓ What are the current visiting days and times for my loved one’s housing unit?
- ✓ Are there any temporary restrictions or changes that affect visits right now?
- ✓ What ID and dress code rules are being enforced for visitors?
- ✓ Are there any current health-related requirements for visitors?
- ✓ Can you confirm my loved one’s housing unit before I travel?
- ✓ If I’m mailing something, what is the correct mailing address format to use?
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