What is the difference between time in service (TIS) and time in grade (TIG)?

• A. TIS is time in service; TIG is time in grade.
• B. TIS is time in service; TIG is time in grade.
• C. TIS is only time in rank.
• D. TIG is total service time.

Answer: (C)

The idea being tested is how time measurements are used for promotions: total service time versus time in the current rank. Time in service is the overall length of time a member has served in the military from entry onward, counting all ranks held along the way. Time in grade is how long a member has held the current rank; it does not include time spent in earlier ranks. When you’re promoted to a new rank, time in grade typically resets to zero and starts counting again in the new rank.

So, the statement that time in service is only time in rank isn’t correct. Time in service covers the whole career, while time in grade is specifically the duration in the present rank. Both measures can influence promotion decisions, but they refer to different periods of time.