MDC Brooklyn Inmate Search

The Gap Between Arrest and the Locator

This is the thing to understand before anything else.

A federal arrest puts someone in the custody of the U.S. Marshals Service. The Marshals hold and transport people through the court process. The Bureau of Prisons locator does not cover them.

Only when the Bureau receives someone into a facility does a record appear. At MDC Brooklyn, Receiving and Discharge accepts pretrial arrivals weekdays from 8:00 AM to 3:00 PM and from 8:00 AM at weekends, and intake housing runs about a week before a person moves to a general unit.

So there is a real interval, sometimes days, when the person exists in the federal system and not in the search.

The Bureau’s own advice reflects this. Its guidance on sending money says to wait until a person has physically arrived at a Bureau facility before sending funds. That is the same warning in a different costume.

How to Run the Locator Search

Two ways in.

By register number. The format the locator wants is five digits, a dash, three digits, written as #####-###. This is the number that identifies a person across the whole federal system, and it does not change if they move.

By name. First and last name, with optional race, age and sex to narrow a common name.

The locator also accepts DCDC, FBI and INS numbers, which are the identifiers other agencies use.

The Register Number Has Two Formats and Both Are Correct

This costs families money, so it is worth being explicit.

Where	Format	Example
The inmate locator	Five digits, dash, three digits	12345-678
Every money transfer	Eight digits, no dash or space	12345678
MoneyGram and Western Union account field	Eight digits then the surname, no space	12345678DOE

The locator shows you the dashed form. Every deposit route wants the undashed one. A money order with the dashed number on it, or with a space in the account field, is a deposit that has to be chased.

What the Result Tells You

The record gives the person’s register number, age, race, sex, release date where one is set, and current location.

What it does not give you is a housing unit, and at MDC Brooklyn that matters more than usual. Visiting here runs on a per-unit schedule, and the Bureau’s guidance is explicit that the institution will not tell a visitor which day and time applies. That information has to come from the person themselves.

Reading Released or Not in BOP Custody

The Bureau publishes a caution here that is easy to misread as good news.

If a person is listed as Released or Not in BOP Custody with no facility shown, they are no longer in Bureau custody. The Bureau adds that they may still be in the custody of another correctional system, criminal justice system or law enforcement agency.

At a detention centre in particular, that status often means a transfer rather than a release: to a designated prison after sentencing, to state custody, or back to the Marshals for a court appearance elsewhere.

Five Reasons the Search Comes Back Empty

1. They are still with the U.S. Marshals, not yet booked into the Bureau. Most common by a distance.
2. They are in state or city custody. Someone at Rikers Island is in New York City Department of Correction custody, with a separate lookup. Someone in a New York state prison is in the DOCCS system, with another.
3. The name on the record differs from the name you use. Try the surname alone.
4. They have been designated and moved to another facility. The record follows them, so search by name nationally rather than assuming Brooklyn.
5. The record predates 1982, which is as far back as the locator goes. Rare, but it exists.

Why This Building Turns Over So Fast

MDC Brooklyn is not a place people settle. The Bureau describes it as a short-term facility for pretrial and unsentenced detainees going through the judicial process, and notes that most people here, if sentenced, will serve that sentence at a different institution.

The scale of the churn is worth knowing: Health Services screens 200 to 300 newly arrived people every week against a population of 1,266 recorded on September 10, 2026.

The practical consequence for a family is a habit rather than a fact. Check the locator before you travel, before you post a letter, and before you send money. At a prison, a person’s location is stable for years. Here it may not last the month.