Milestone billing without the spreadsheet

Fixed-fee project work is the revenue model spreadsheets survive longest in, because every engagement looks like an exception. Picture 6 live SOWs worth $9.6M, each with its own milestone schedule and amendments that move the totals mid-flight.

Three things that broke

• Percent-complete revenue recognised off a schedule nobody updated after an amendment
• Amendments tracked in a separate tab and applied from memory
• Invoices raised on the milestone date rather than on client acceptance

The schedule was right the day it was written and drifted every week after.

What replaced it

Milestones now carry their own state, not started, in progress, awaiting sign-off, paid, and the invoice is raised by acceptance, not by calendar. Amendments version the SOW rather than overwriting it, so the recognition schedule follows the work instead of the original plan.

Each acceptance raises its invoice and recognises its revenue in one step, which turned a quarterly reconstruction into a balance that is simply correct.