Billing Milestones, Work in Progress, and Where Margin Quietly Leaves
Work in progress is the politest term in professional services. It means work you have done and not yet been paid for, and it is where margin goes to die.
Between a consultant recording an hour and a firm holding the cash there are four transitions, and value can be lost at each. The hour becomes work in progress. Work in progress becomes an invoice. An invoice becomes cash. And at any point along that path, somebody can decide the amount will not be collected and write it off.
Firms measure the beginning and the end well. Time recording is usually rigorous and cash collection is watched closely because the bank balance is visible. The middle two transitions are where the money actually leaks, and they are the ones least often instrumented.
The states a billing milestone moves through
- Pending: agreed in the contract, not yet earned. The work behind it has not been done or the trigger has not occurred.
- Earned: the condition is satisfied and the firm is entitled to invoice. This is the state most firms cannot see, and the gap between earned and invoiced is pure delay in the firm's own control.
- Invoiced: sent to the client, and the payment clock has started.
- Paid: settled.
- Disputed: the client has objected. Different from unpaid, because an unpaid invoice is a collection problem and a disputed one is a delivery or expectation problem wearing a finance costume.
- Held: the firm has chosen not to invoice yet, usually for relationship reasons. Legitimate, and dangerous when nobody revisits it.
- Written off: the firm has decided it will not collect. This should be a deliberate act with a reason and an owner, not a reconciliation adjustment.
The gap between earned and invoiced
This is the cheapest money in professional services and most firms leave it on the table. Work that has been done, is contractually billable, and has not been invoiced is a loan the firm is making to its client at no interest, and the size of it is usually a surprise when first measured.
The causes are mundane. Billing happens monthly in a batch, so a milestone earned on the second waits four weeks. Nobody noticed the milestone was earned because it depends on a deliverable being accepted and the acceptance was verbal. The partner wants to bundle it with the next one to avoid a small invoice. Each is defensible and together they add weeks to the cash cycle at no benefit.
The fix is visibility rather than policy: a list of milestones that are earned and not invoiced, with an age against each, reviewed at the same cadence as collections. Firms that start reporting this are usually billing faster within one cycle, without changing any rule.
Held is where the danger is
A milestone on hold is the firm choosing not to invoice, and the reasons are almost always relationship management: an unresolved complaint, a delivery problem, a negotiation in progress. Every one is a reasonable decision on the day it is taken.
What makes hold dangerous is that it has no natural end. Nothing forces a review, the amount stays on the books as an asset, and six months later somebody discovers a substantial balance held for a reason nobody remembers, against a client relationship that has since changed. At that point it is written off, and a write-off six months late is a write-off that was never managed.
Every hold should carry a reason and a review date, and a report of holds past their review date should reach whoever owns the relationship. That single control converts a hidden loss into a decision somebody takes on purpose.
Writing off deliberately
A write-off is a decision to stop pursuing value the firm earned. Treated as an accounting adjustment at period end it is invisible as management information. Treated as a decision it is one of the most informative numbers a firm has, because it says where the business is systematically failing to convert work into money.
What makes it useful is requiring both an amount and a reason at the moment of the decision, and then reading the reasons in aggregate. A quarter of write-offs attributed to scope disputes points at the proposal stage. A quarter attributed to quality points at delivery. A quarter attributed to client financial difficulty points at acceptance, which should have caught it. Without the reasons the total is just a number that makes people unhappy.
Reading the numbers as one picture
- Work in progress by age, because unbilled work older than a quarter is unlikely to be billed at full value.
- Earned but not invoiced, with age, reviewed alongside collections rather than separately.
- Held balances past their review date, reported to the relationship owner.
- Write-offs by reason, in aggregate, quarterly, read as a diagnosis rather than a total.
- Disputed invoices separated from overdue ones, because they need delivery attention rather than a collections call.