Phi Theta Kappa sends out invitations to associate degree seeking, full time students who have completed 12 or more credit hours. Once you gain membership, you must maintain a 3.2 or higher GPA to remain a member. E-mailed and mailed invitations with your membership acceptance code are sent every fall, spring, and summer semester to eligible students. Students who wish to join the honor society must accept membership online at join.ptk.org/. Lifetime Membership into Phi Theta Kappa costs a one-time fee of $85.