By TIM · August 2026 · 8 min read
Cost-to-complete (CTC) forecasting estimates the remaining cost to finish an active project at any given point — not what has already been spent, but what the job will cost in total by the time the final invoice goes out. For high-ticket service businesses running five to fifteen simultaneous projects, CTC is the difference between catching a margin problem in week two and discovering it in week fourteen when the loss is already locked in. Most service businesses track backward — what was spent — but the decisions that save or lose margin are made on what is about to be spent. Job costing tells you the autopsy. Cost-to-complete forecasting is the diagnosis while the patient is still on the table.
Job costing is a critical practice. Tracking actual costs against estimated costs per project is how a service business stops guessing and starts managing. But job costing, by design, is backward-looking — it tells you what has happened on a project, not what is going to happen.
The problem is structural. A twelve-week remodeling project that closes at 9% margin instead of the estimated 22% did not fail at week twelve. It failed at week four, when the tile phase ran 14 hours over budget. It failed at week six, when a subcontractor invoice arrived $2,200 above the original quote and was approved without a change order. It failed at week eight, when three days of crew hours were absorbed by a scope change the client requested verbally during a walkthrough.
Each of those events had a recoverable window — a moment when the trajectory could have been changed, a conversation that could have happened, a change order that could have been issued, a crew reallocation that could have protected the margin. The window closed not because the information was unavailable but because nobody was calculating what the job was now going to cost at completion.
That is what cost-to-complete forecasting fixes.
Cost-to-complete is not a complex calculation. It requires three inputs per project and produces one number: the projected final cost, which you compare directly to the contract value to get your projected final margin.
| Input | How to Get It | What It Tells You |
|---|---|---|
| Costs incurred to date | Sum all labor hours logged × burdened rate + all material invoices received + all sub invoices paid or approved | What the project has already spent — this is your backward-looking baseline |
| Cost-to-complete estimate | (Remaining labor hours × burdened rate) + (remaining material purchases not yet ordered) + (remaining sub work not yet invoiced) | What the project is going to spend from today to close — this is the forward-looking variable |
| Projected final cost | Costs incurred to date + cost-to-complete estimate | Compare to contract value: (Contract value − Projected final cost) ÷ Contract value = Projected final margin % |
Example: A $95,000 kitchen renovation is at week six of fourteen. You have spent $47,000 to date. Your cost-to-complete estimate for the remaining eight weeks — based on budgeted hours for remaining phases, pending material orders, and sub work not yet invoiced — is $38,000. Projected final cost: $85,000. Projected final margin: 10.5%.
Your original estimated margin was 21%. You now have eight weeks to understand why 10 points are missing — and whether any of it is recoverable.
That conversation happens at week six, not week fourteen.
Most margin problems are visible before they are irreversible. These are the three indicators that a project's cost-to-complete is worse than your estimate assumed:
1. Percent-spent versus percent-complete divergence
This is the fastest single diagnostic available. If a project has consumed 65% of its budget but is only 45% complete by scope, the remaining work will cost more than what is left in the budget — guaranteed. The divergence is the warning. The wider the gap, the larger the projected overrun.
Run this number on every active project weekly. If percent-spent is more than 10 points ahead of percent-complete, treat it as a red flag that requires a full CTC recalculation.
2. Labor hour burn rate exceeding phase estimates
Labor is the hardest cost to track and the most common source of CTC variance. When a phase that was estimated at 24 hours has consumed 31 hours at the halfway point, the final labor cost for that phase is not tracking to estimate. See how labor hour variance compounds across an active project schedule for the math on what three-hour overruns per phase produce across a twelve-week job.
3. Subcontractor invoices arriving above original quotes
Every subcontractor invoice that arrives above the quoted amount is a CTC variance event. It does not reduce the contract value — the client does not absorb it unless a change order was issued. The difference comes directly out of the margin. Track sub quotes against actual invoices on a per-project basis throughout the job, not at reconciliation. By the time you see a $3,400 variance on a final invoice, the window for recovering it has closed. See how the actual versus quoted margin gap develops job by job for the pattern this creates across a full year of projects.
A functional CTC review does not require sophisticated software. It requires five questions asked about every active project, once per week.
| Question | What You're Looking For | Action Threshold |
|---|---|---|
| What is the percent-spent vs. percent-complete gap? | More than 10 points of divergence = the project is burning faster than it is building | Recalculate full CTC; identify the overrunning phase |
| Are any labor phases tracking above their hour budget by more than 15%? | Indicates the phase estimate was wrong or the work is taking longer than planned | Review remaining labor for that phase; adjust the CTC estimate upward |
| Have any sub invoices arrived above the original quote? | Each dollar above the quoted amount is unrecovered cost unless a change order was issued | Flag immediately; issue a change order or absorb the variance knowingly |
| Are there any verbal scope changes from the client that haven't been priced? | Unpriced scope = unpaid labor and material that will show up in final cost | Issue a change order before the work begins; never price it after the fact |
| Is there any pending material order that has changed in price since the estimate? | Material price escalation since the bid can shift the CTC significantly on large orders | Reprice the order; assess whether a change order or contract escalation clause applies |
If all five answers are clean — no divergence, no variance, no unpriced scope — the project's CTC is tracking to estimate. If any answer triggers the threshold, the CTC needs to be recalculated and a decision needs to be made before the next phase begins.
This review takes 15 to 20 minutes per active project when run weekly. It takes significantly longer when run only at project close — because at that point, the answers do not produce decisions. They produce explanations.
Running a weekly CTC review across eight to twelve active projects requires a reliable data collection system. The review is only as accurate as the underlying numbers — labor hours logged by task and project, material invoices categorized correctly, subcontractor invoices matched to original quotes, change orders documented and linked to the estimate.
TIM's Operations Manager monitors every active project simultaneously, with 40 conditions tracked across every job. Every time a project stage closes, TIM compares budget to actual at the stage level — and flags immediately if actual costs exceed the budget by more than 10%. That stage-level comparison is the building block of a real-time CTC calculation: the variance at each completed stage tells you how the remaining stages need to be recalibrated.
The morning briefing TIM generates before 8 AM each day includes project-by-project status across every active job: what closed yesterday, what is opening today, what has triggered a flag, and what is on the critical path. A business running ten active projects does not need a dedicated project manager to know the cost position of each job — it needs a system that is monitoring all ten simultaneously and surfacing the numbers that require a decision.
TIM is Digital Labor — a business operating system for US service businesses with 1 to 15 employees running high-ticket projects. TIM handles the project surveillance, the stage-by-stage profitability tracking, the change order detection, and the morning briefings that make a weekly CTC review possible without adding hours to the owner's schedule.
TIM is priced against the $4,000/month salary of the project administrator role it replaces, not against $20/month software. For a business running eight to twelve active projects, that comparison becomes straightforward when the alternative is one owner trying to hold the cost position of twelve jobs in memory while also running field operations, client calls, and new estimates.
For the full picture of what TIM tracks across an active project: see how it works.
Cost-to-complete forecasting does not require a system change to begin. Pick two active projects. Run the five questions above on each one. Calculate the percent-spent versus percent-complete gap. Look at every sub invoice received in the last four weeks and check it against the original quote.
What you find will tell you whether the current trajectory produces the margin you estimated — or whether the conversation needs to happen now, before the work is finished and the loss is permanent.
For more on the real-time tracking infrastructure that makes this sustainable across every active project: see TIM's approach to project profitability. And if you are ready to build the system: see if there is a fit.