Managing Side Letters Alongside Your Main CBA

Side letters and MOUs often modify wages, schedules, or working conditions for specific units. Ignoring them during proposal review leads to incorrect risk assessments — especially when management cites “the CBA” while relying on a narrower letter that actually controls.

Inventory every active side letter before bargaining: effective dates, covered classifications, and whether the letter sunsets with the master agreement. Expired letters still confuse committees if they remain in shared drives without labels.

Union Boss supports side letter uploads alongside your main CBA on Local plan and above. All clauses are searched together when analyzing new management proposals, so overtime or staffing conflicts that live only in a letter still surface.

Remove outdated side letters from your workspace when they expire so analysis reflects only active terms. When a letter is renewed with edits, replace the file rather than stacking duplicates that disagree.

During negotiations, treat proposals that “incorporate prior practice” carefully. Ask whether practice is memorialized in a side letter; if not, analysis against the master CBA alone may understate risk for the affected unit.