Add, count (3,2)
I believe the answer is:
tot up
I believe this clue is a double definition.
'add' is the first definition.
(I know that add can be written as tot up)
'count' is the second definition.
(to tot up is to count or add up)
(Other definitions for tot up that I've seen before include "Add together (driving offences)" , "Sum - total" , "Add (some numbers)" , "Tally" , "Determine the sum of" .)