Why Basecamp's Flat-Fee Model Protects Agency Retainer Margins

Basecamp's Pro Unlimited plan at $299/month flat means an agency can add every client stakeholder and contractor to a shared workspace without a single per-seat charge, which is the opposite of how most project management tools price. For agencies running client-facing retainers, that turns a variable delivery cost into a fixed line item that gets cheaper per head as the account grows. The strategic question is not whether Basecamp has the deepest feature set, but whether predictable seat-free pricing lets you scope retainers more aggressively than competitors who bill per user.