Share out area tax returns (5)
I believe the answer is:
allot
'share out' is the definition.
(allotting is a kind of sharing out)
'area tax returns' is the wordplay.
'area' becomes 'a' (maths abbreviation).
'tax' becomes 'toll' (I've seen this in other clues**).
'returns' is a reversal indicator.
'toll' written backwards gives 'llot'.
'a'+'llot'='ALLOT'
(Other definitions for allot that I've seen before include "Hand out" , "Assign (to someone)" , "Give as a share, or a task to be done" , "Distribute in portions" , "Dispense or distribute" .)