The institute is currently paid a substantial fee - understood to be tens of thousands of pounds - to endorse the company as an adviser.
Sector Treasury Services was formed after its parent, Sector Holdings, acquired Integer and then took over UBS's public sector team last September. Sector Treasury Services inherited the CIPFA endorsement from Integer.
CIPFA chief executive David Adams indicated earlier this year the relationship would be reviewed. The review has now been concluded.
Mr Adams said: 'Sector and Cipfa have completed the review and we now need to decide how to announce it. This very long saga is about to end.'
Sector's managing director, John Luke, declined to comment on whether it would retain the Cipfa endorsement.