A 100-day plan is the first operational blueprint after a deal closes or a new leader starts—typically a numbered list of priorities, owners, and weekly milestones for roughly the first hundred days.

How it works

Private equity buyers and strategic acquirers often ask management to draft a 100-day plan before or immediately after close. The document usually splits work into quick wins (keep customers, stabilize billing, retain key engineers) and longer bets (pricing changes, cross-sell, cost consolidation). Each line item gets an owner, a metric, and a check-in rhythm—often weekly steering meetings with the board or deal team.

Venture-backed companies use the same idea when a growth investor takes a board seat after a large round, or when a founder CEO transitions to executive chair. The plan is not a fantasy strategy deck; it is a working calendar. If you cannot explain what changes in week six versus week twelve, the plan is too vague.

Why it matters

• Founders: A clear 100-day plan protects your team from post-close whiplash. It gives you leverage to push back on ad hoc requests that were not in diligence.
• Investors: The plan is a early signal of operator quality. Missed milestones in the first ninety days often predict integration problems later.
• Operators: It turns abstract synergy slides into weekly tasks finance and product can actually execute.

Common mistake

Treating the 100-day plan as a marketing document for the acquirer instead of an internal operating tool. If sales, finance, and engineering never see the same version, the plan becomes shelfware the moment the press release goes out.

Related ideas

Post-merger integration, change management, synergy capture, and acquisition governance all overlap here. In venture, the closest cousin is a ninety-day board plan after a Series B—same discipline, smaller scope.