Letters to inmates

How do you mail a letter to an inmate?

Updated November 12, 2026 · By the SendMyLettersOnline team

Look up the person on the official inmate locator to get their full committed name, inmate or register number and facility, then address the envelope to that name and number at the facility's published mailing address, with your full name and return address on the envelope. Before you send, read the facility's mail rules: letters with missing ID numbers, no return address or banned items (stickers, glitter, stains, staples, some photos) are returned or destroyed.

Every prison and jail sets its own rules, and they change. Federal prisons follow Bureau of Prisons policy; state prisons follow the state Department of Corrections; county jails follow the sheriff. The facility's own page is the final word.

Where to find the address and rules
Facility type	Find the person	Mail rules come from
Federal prison	BOP inmate locator (gives the register number)	Bureau of Prisons policy and the facility page on bop.gov
State prison	The state Department of Corrections inmate search	The state DOC's mail or correspondence page
County or city jail	The sheriff's or jail's inmate search	The jail's website or the sheriff's office
Immigration detention	ICE Online Detainee Locator	The detention facility's page

How to address the envelope

Name line: the person's full committed name (the name on the locator, not a nickname) followed by their inmate or register number.
Facility name, then the mailing address exactly as the facility publishes it. Many facilities use a PO Box or a separate mail-processing address that is different from the street address.
Your return address: full name and full street address. Most facilities refuse mail without one.
Use a plain white envelope and a regular stamp. No labels, stickers or drawings on the outside.

Rules that apply almost everywhere

Assume staff will open and read the letter (legal mail from an attorney is handled differently).
No cash, checks, stamps, stickers, glitter, perfume, lipstick, crayon or anything glued on.
No content about escapes, crimes, threats, codes or other inmates.
Photos, cards, books and magazines have their own rules; many facilities ban them or require them from a publisher.
Some facilities accept only postcards, or require personal mail to go to an off-site scanning address; others offer facility-approved electronic messaging instead.

If you don't have a printer, stamps or envelopes

You can type the letter online and have it printed and mailed for you. We print on plain white paper, mail it in a standard envelope by USPS First-Class Mail and put your return address on it. Check first that the facility accepts typed letters from a mailing service: a few require handwritten mail, postcards only, or mail sent through a specific vendor. We don't send photos.

Quick answers

What are the rules for mailing letters to inmates?

They are set by each facility. Almost all require the inmate's full name and ID number, your full return address, and no added items such as stickers, glitter or cash. Read the facility's mail page before sending; see federal prison mail rules and state prison mail rules.

Can you type a letter and mail it to a prisoner?

Usually yes. Most facilities accept typed letters on plain white paper, but a few restrict mail to postcards, handwritten letters or an approved vendor. Check the facility's rules, then you can write the letter online and we print and mail it.

Do I need the inmate number to send a letter?

In practice yes. Facilities sort mail by ID number, and many return mail that doesn't include it. Federal register numbers are on the BOP inmate locator.

Can I send photos to an inmate?

Depends on the facility; some allow a limited number of printed photos, some only through an approved service, some none. We don't send photos. See sending photos to an inmate.

What to do next

Checked the facility's rules? Open the inmate letter template, type your letter, and we print it and mail it First-Class with your return address.

Write a letter to an inmate

Sources

Checked: November 12, 2026. General information, not legal advice. Fees and rules change: confirm current values at the official links above.