List benefits, initially, in account (5)
I believe the answer is:
table
'list' is the definition.
(I've seen this before)
'benefits initially in account' is the wordplay.
'initially' suggests taking the first letters.
'in' is an insertion indicator.
'account' becomes 'tale' (tale is a kind of account).
The first letter of 'benefits' is 'b'.
'b' going into 'tale' is 'TABLE'.
(Other definitions for table that I've seen before include "Put forward for formal discussion" , "Data arranged in rows and columns" , "Index" , "Flat-topped piece of furniture" , "Dummy hand (bridge)" .)