There is no single GPA (grade point average) that assures you of being hired by a CPA firm. I have seen firms pass over a student with a near-perfect GPA (3.97 out of 4.0) and hire a student with a 3.2 GPA. This occurred because the student with the 3.97 GPA had demonstrated that he could study but could not relate comfortably with others. The student with the 3.2 demonstrated that he could chair a student/CPA firm dinner and was comfortable being the emcee for the evening. Apparently the recruiters were concerned with having the first student meet with their clients and were impressed with the second student.
Some firms will accept a lower overall GPA if there is an upward trend in the GPA and/or if the GPA for the accounting courses is greater than the overall GPA. One recruiter told me that his firm will not allow him to even consider a student that has earned less than a "B" in any accounting course.
The rigor of the college accounting program can also be a factor. For instance, a student earning a 3.7 GPA in a college where half of the grades are A's will not be as impressive as a student earning a 3.4 GPA in a college where only 20% of the grades awarded are A's.
In short, the GPA needed to be hired by a CPA firm will depend on the philosophy, size, and clients of the CPA firm. The required GPA will also depend on the student's ability to work with others, to lead, and to pass the CPA Exam. Other factors will be the student's work experience, outside activities, and more.