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Truviate

Billing Preflight

What Is Billing Preflight?

Definition

Billing Preflight is an independent verification step performed before a client invoice is sent. It compares the commercial agreement, approved work, applicable expenses and draft invoice to identify supported billing gaps that require review.

Acme CorpAugust 2026

Running

  1. Agreement

  2. Approved work

  3. Draft invoice

  4. Calculation

  5. Result

Sample data

What it is

A preflight is a fixed check before an irreversible step. Here the irreversible step is sending the invoice: once a client has received and paid it, re-opening the period for an amount that was left off is awkward for everyone.

A Billing Preflight asks one narrow question. Given the billing rules confirmed from the agreement, and the work and expenses approved for the period, does every supported billable amount appear on the draft invoice?

What it is not

  • Not invoicing or accounting software — it never edits or sends an invoice.
  • Not a PSA, project management tool or time tracker — it reads their exports.
  • Not autonomous accounting AI — AI proposes terms, a person confirms them, deterministic code calculates money.
  • Not a revenue-recovery guarantee — when the evidence is incomplete it says so.
  • Not a detector of unlogged time, weak pricing or slow collections.

How it works

  1. Extract commercial rules. The agreement or SOW is read, billing terms are proposed with their source clause, and a person confirms each rule.
  2. Verify against actual delivery. Approved time entries, milestone evidence and applicable expenses are matched to the confirmed rules for the period.
  3. Compare with the draft invoice. Each supported amount is classified as present, missing, needing review or lacking evidence — with an Evidence Trace.

Billing Preflight vs invoicing

Invoicing software checks the lines that made it onto the invoice: totals, tax, numbering. A Billing Preflight checks what should have been on the invoice according to the agreement and the approved work. It happens before invoicing and produces findings, not documents.

Billing Preflight vs PSA

A PSA runs the delivery: projects, time, resourcing, often the invoice draft itself. A Billing Preflight is an independent control on the output of that system. It uses the PSA’s exports as evidence and compares them with the contract; it does not replace the PSA and does not write back into it.

Examples

  • Retainer overage. The agreement includes 40 hours a month at a $175/hour overage rate; 48.5 hours were approved; the draft carries the retainer line only. 8.5 × $175 = $1,487.50, classified VERIFIED_MISSING.
  • Reimbursable expense. An approved third-party licence at cost is absent from the draft. Its receipt, approval and the agreement clause are present: VERIFIED_MISSING.
  • Milestone. A $7,500 milestone is billable after deployment and written acceptance. Deployment is evidenced, acceptance is not: NEEDS_REVIEW, amount affected, nothing verified.

Illustrative product examples based on Truviate regression scenarios — not customer claims.

Illustrative finding

8.5 approved hours beyond the 40 h allowance; $1,487.50 is not on the draft invoice.

The clause is confirmed, the hours are approved, the arithmetic is deterministic, the draft was compared and no credit, ambiguous line or unapproved row contradicts it.

Evidence available
  • Confirmed contract rule
  • Approved work or expense evidence
  • Amount computable from confirmed inputs
  • Draft invoice compared
  • No conflicting evidence
Evidence missing or uncertain

Nothing — every item of the checklist is satisfied.

Verified missing

+$1,487.50

Supported by the confirmed rule, the approved evidence and the draft comparison. The only figure that may be called missing.

Why this state

Every checklist item is satisfied and no conflict exists. The amount may be reported as verified missing.

A person still decides how the invoice is handled; Truviate never edits it.

States are decided by the evidence policy, never by a confidence score. Sample data.

Limitations

  • Only the rule families supported today are verified: retainer with overage, time and materials, reimbursable expenses, milestones.
  • The check is as good as the evidence exported to it. Unapproved rows are listed, not counted.
  • Findings are decided by an evidence policy, not by a confidence score. When evidence is missing the answer is NEEDS_REVIEW or INSUFFICIENT_EVIDENCE.
  • Truviate does not estimate what an agency loses. It reports what the evidence supports for one billing cycle.

Who needs it

  • Software, web and IT services agencies billing several clients every cycle
  • Retainers with overage, time and materials, milestone or mixed billing
  • Evidence spread across project, time and accounting tools
  • A finance review that is still partly manual

Test it on one real billing cycle.

Your first full Billing Preflight is free. If nothing meaningful is found, Truviate says so.

Request a Free Billing PreflightExplore the sample preflight

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