Everything's bound to go round — that's agreed (7)
I believe the answer is:
tallied
'agreed' is the definition.
('tally' can be a synonym of 'agree')
'everything's bound to go round' is the wordplay.
'everything' becomes 'all' (all things).
'bound' becomes 'tied' ('tie' can be a synonym of 'bind').
'to go round' indicates putting letters inside.
'all' going within 'tied' is 'TALLIED'.
'that's' acts as a link.
(Other definitions for tallied that I've seen before include "Agreed, corresponded" , "Corresponded - kept score" , "Reckoned debt or score" , "Agreed; calculated" , "Matched" .)