The biggest difference is who sets the rules: a jail is run locally, usually by a county sheriff, so its mail rules can change from one county to the next, while a prison is run by a state corrections department or the federal Bureau of Prisons, so one set of rules covers every prison in that system. That changes the ID number you write, where the envelope goes, how many photos you can send and what your loved one actually receives.
Here's how sending mail and photos differs, and what stays the same.
Jail vs. prison in one minute
The U.S. Bureau of Justice Statistics describes jails as locally operated, short-term facilities that hold people awaiting trial or sentencing, and people sentenced to a year or less. They're usually run by a sheriff, a police department or a county or city administrator. Prisons hold people after conviction, are run by a state Department of Corrections or the Federal Bureau of Prisons (BOP), and typically hold people serving more than a year.
BJS also notes that definitions vary by state. Someone can be in a jail after sentencing while waiting to move to prison, and some county jails hold people for ICE or federal authorities too.
The ID number: temporary vs. permanent
This is one of the easiest things to get wrong.
- Jail: mail usually needs a booking number, and that number changes every time someone is booked. An old booking number from a past arrest won't work.
- State prison: the person gets a state number that follows them through that state's system, such as a TDCJ number in Texas or a DIN in New York.
- Federal prison: everyone has an 8-digit Register Number (like 12345-678) that stays with them. You can find it with the BOP inmate locator.
When someone moves from jail to prison, the booking number stops being useful and you'll need their new number. Our how-to guide lists where to look up each type, and our post on finding an inmate ID number walks through it step by step.
Where the envelope goes
A jail's mailing address is set by that sheriff's office. Many jails take mail at the building; others use a P.O. box or send mail to an outside scanning service first. A typical jail address looks like this:
[Full name] [Booking Number]
[JAIL NAME]
[JAIL MAILING ADDRESS]
[CITY STATE ZIP]
Prison systems are more likely to send all personal mail to one central address for the whole state. Texas is a good example. The TDCJ digital mail page says personal mail for all units goes to a processing center in Dallas, and our Coffield Unit page shows the format:
TEXAS DEPARTMENT OF CRIMINAL JUSTICE
[Full name] [TDCJ Number]
PO BOX 660400
DALLAS TX 75266-0400
Pennsylvania and Florida also send state prison mail to central mail centers, and federal prisons each have their own inmate mail address, usually a P.O. box rather than the street address.
Photo rules: set locally vs. system-wide
Jail rules are made county by county, so they vary more, and some are strict. A few official examples:
- Broward County, Florida: the Broward Sheriff's Office moved to postcard-only routine mail in 2021. Envelopes and letters aren't accepted, photos must be printed on the postcard itself, and postcards showing the person receiving them aren't allowed.
- Santa Barbara County, California: the sheriff's mail rules allow up to five photos per envelope, no larger than 4x6, with "PHOTOGRAPHS" written on the outside and the person's name, booking number and CID number on the back of each photo.
- Yuba County, California: the jail's mail page says photographs may not exceed 3 by 5 inches.
Prison rules apply across the system. Florida's state prison rule, for example, allows photos up to 8x10 and bans Polaroids. Tennessee's state prison mail policy also bans Polaroid-type pictures. The federal Bureau of Prisons sets national rules (no nude or sexually explicit photos) and lets each prison add local limits.
What's banned is broadly similar everywhere: nudity, sexual content, gang signs, weapons, drugs and money. Our post on what photos are allowed covers the details.
What your loved one receives
Both jails and prisons increasingly copy or scan mail instead of handing over the originals:
- Federal prisons: most give the person a color copy of each photo. Minimum-security facilities generally still deliver prints. See our federal prison guide.
- State prisons: Texas scans mail to tablets (with black-and-white printouts for people without one). Michigan's Department of Corrections says it photocopies incoming personal mail in black and white and shreds the originals.
- Jails: it varies widely. Some hand over prints, some use outside scanning services and some, like Broward, only take postcards.
Moves happen faster in jail
People in jail move often: to court, to another county, or to a state prison after sentencing. Prison transfers happen too, but the person usually keeps the same state or federal number. Confirm where someone is shortly before you send, especially if they're in jail. Our post on what happens to mail after a transfer explains what each system does with mail that arrives after someone leaves.
Tips that work for both
- Look up the current location and number right before you send.
- Use the facility's mailing address, not just the street address you find on a map.
- Stay under the photo limit per envelope. Going over can get the whole envelope rejected.
- Send real photo prints, not plain-paper printouts or Polaroids.
- Put your full return address on the envelope.
How InmatePics handles the difference
You choose the facility, jail or prison, and we handle the rest: the right address and ID format, real 4x6 prints, and splitting your order into envelopes the facility will accept. Before you pay, we tell you whether the person will get prints, a copy or a tablet scan. You can browse every facility by state in our facility directory.
Frequently asked questions
Is county jail the same as prison?
No. Jails are run locally and mostly hold people awaiting trial or serving short sentences. Prisons are run by states or the federal government and hold people serving longer sentences.
Can I send photos to someone in jail who hasn't been sentenced?
Yes. Jails accept photos for people awaiting trial, as long as you follow the jail's rules. Some jails only accept postcards, so check first.
Do I need a new address after they're sentenced?
Usually, yes. If they move to a state or federal prison, you'll need the new facility's mailing address and their new ID number.
Which has stricter mail rules, jail or prison?
It depends on the place. Some jails have stricter rules than many prisons (postcard-only, for example), while some prison systems send everything through central scanning. Always check the specific facility.
