28 CFR §540.11
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
The Warden shall establish at least one mail depository within the institution for an inmate to place outgoing correspondence. The Warden may establish a separate mail depository for outgoing special mail. Each item placed in a mail depository must contain a return address (see § 540.12(d)).