This study explored the letter-writing practices of incarcerated adult students at a facility within the Los Angeles County jail system. The study sought to understand the role that letter writing plays in the lives of these individuals, their unique composition processes and products, their beliefs about themselves and their skills as writers, and the assets and strategies they use in this literacy practice. For this qualitative study, I interviewed twelve individuals currently or recently enrolled in an adult secondary education program offered by the Los Angeles Sheriff’s Department and a local charter school. During the interviews, participants provided self-selected, handwritten letters to explain and explore their letter-writing processes. The interviews and documents reveal that letter writing, while practically non-existent in contemporary society and their lives on the outside, plays a vital role in participants’ carceral experience; most participants wrote their first letter while incarcerated, and many have since developed a strong letter-writing practice and routine. The study reveals that letters and letter writing function as a medium for participants to connect with loved ones and express themselves in ways other forms of communication—namely phone calls and visits—do not provide. Letters provide participants with opportunities to make sense of their carceral experience and themselves in the process, and letters, as tangible objects, function as gifts and personal legacies for recipients on the outside. As students, participants utilize the classroom, their classmates, and instructors to compose and develop their letters, and the authentic practice of letter writing has led to the development of literacy skills over time. The insight, honesty, and vulnerability shared by these participants, both in the interviews and through their personal letters, provide a glimpse into the unique phenomenon of letter writing in the understudied context of jail.