A report said early retirement and voluntary severance (ERVS) and flexible retirement had helped cut numbers.
It has seen full-time equivalent posts cut from 6,025 in April 2015 to 5,353 a year later - a reduction of 672.
The number of vacancies has also been reduced over the same time period from 546 to 466.
In addition, the report to councillors details the number of days being lost due to sickness among council staff.
It shows an average of more than 12 days were lost due to illness per full-time employee which exceeds a national target of nine days.
However, the local authority is meeting its target for teacher absences which sit below seven days per full-time post.
Dumfries and Galloway Council has reduced its staff numbers by the equivalent of more than 600 full-time posts in the space of a year.