The agreement involves all print and production workers, which totals nearly 40, at the Bristol facility, part of the USA-based multi-national packaging company Chesapeake Group.
Unite regional officer Steve Smith told printweek.com: "This agreement give the staff at Chesapeake a voice at work; it's a turning point for Unite's members at the company".
The agreement means Chesapeake will have to consult union representatives prior to making decisions that can effect the working terms and conditions of its employees.
He added: "Reps from the company will be elected and Unite will now be present at consultation meetings held at the site."
"Chesapeake has been very co-operative and accepted that Unite membership levels at the company were high enough to open voluntary agreement discussions," Smith said.
Unite National Officer, Vernon Robson, added: "Unite reps and members have done a great job in securing union recognition at the site. It shows that having a well run recruitment and organising strategy pays in the long run."
Unite is currently in the process of electing union chapel reps and will then enter into local discussions to put together a local working agreement.