ROI calculator · 7 main inputs
AI automation ROI calculator
Hours saved, annual savings and payback for one workflow, from your own volumes and quote.
Cost per invoice calculator
Cost per invoice is your total monthly cost of processing supplier invoices divided by the number processed. This calculator builds that figure from its parts: minutes per step, loaded rates, exception handling, approver time, late-payment penalties and software. It then estimates the cost per invoice after automation, using assumptions you can change.
Calculate your cost per invoice
Cost per invoice
- Today
- $13.67
- $27,333 a month
- After automation
- $6.64
- Running cost not entered yet
- Saving per invoice
- $7.03
- 51.4% lower
- Annual saving
- $168,640
- $14,053 a month
- Team hours, today
- 458 h
- AP and approvers, per month
- Team hours, after
- 167 h
- Including oversight
Add your running-cost quote to complete the after figure. At 2,000 invoices a month, every $1,000 a month adds $0.50 per invoice.
Where the cost sits, per invoice
Today$13.67
After$6.64
| Group | Today | After |
|---|---|---|
| AP processing | $4.00 | $0.54 |
| Exceptions | $3.17 | $1.80 |
| Approvers | $3.00 | $1.50 |
| Rework and late fees | $1.10 | $0.40 |
| Software, fees and overhead | $2.40 | $2.40 |
An estimate from your inputs. Read the method or work out payback.
Line by line
| Cost line | Today | After |
|---|---|---|
| AP processing time | $8,000 | $1,080 |
| Exception handling | $6,333 | $3,600 |
| Approver time | $6,000 | $3,000 |
| Rework and corrections | $1,000 | $400 |
| Late fees and missed discounts | $1,200 | $400 |
| Software and systems | $2,500 | $2,500 |
| Automation running cost | $0 | Not entered |
| Payment and bank fees | $800 | $800 |
| Overhead | $1,500 | $1,500 |
| Total per month | $27,333 | $13,280 |
| Cost per invoice | $13.67 | $6.64 |
The formulas, with your numbers
Today
- AP processing
- = 2,000 × 6 min ÷ 60 × $40
- $8,000
- Exceptions
- = 500 × 19 extra min ÷ 60 × $40
- $6,333
- Approvers
- = 2,000 × 3 min ÷ 60 × $60
- $6,000
- Other costs
- = $1,000 rework + $1,200 late fees + $2,500 software + $800 fees + $1,500 overhead
- $7,000
- Cost per invoice
- = $27,333 ÷ 2,000 invoices
- $13.67
After automation
- AP review
- = 680 assisted × 1.5 min ÷ 60 × $40 + 10 h oversight × $40
- $1,080
- Exceptions
- = 300 × 18 min ÷ 60 × $40
- $3,600
- Approvers
- = 2,000 × 1.5 min ÷ 60 × $60
- $3,000
- Other costs
- = $400 rework + $400 late fees + $2,500 software + $800 fees + $1,500 overhead
- $5,600
- Running cost
- = Your quote for the new system (not entered)
- $0
- Cost per invoice
- = $13,280 ÷ 2,000 invoices
- $6.64
How to calculate cost per invoice
Count every cost of processing invoices in a month, then divide by the invoices processed. Our cost per invoice guide covers each component in more depth.
- 1
Time each step for a clean invoice
Capture, keying, coding and PO matching, approval routing, posting. Minutes per step × invoices ÷ 60 × the AP loaded rate.
- 2
Add the extra time exceptions take
Exception rate × invoices × extra minutes per exception. Mismatches, missing POs, duplicates and supplier queries all count.
- 3
Add approver time at their own rate
A budget owner who spends three minutes per invoice is part of the cost, even though they never open the AP system.
- 4
Add the money that is not time, then divide
Rework, late-payment penalties, missed discounts, software, payment fees and overhead. Divide the monthly total by invoices processed.
Cost per invoice = ( AP minutes per invoice × invoices ÷ 60 × AP rate + exceptions × extra minutes ÷ 60 × AP rate + invoices × approver minutes ÷ 60 × approver rate + rework + late fees and missed discounts + software + payment fees + overhead ) ÷ invoices processed in the month
A worked example: 2,000 invoices a month
Invented numbers, the same as the calculator's defaults. A clean invoice takes 6 minutes of AP time at $40 an hour. A quarter of invoices are exceptions that take 19 extra minutes. Approvers spend 3 minutes per invoice at $60 an hour.
That comes to $13.67 per invoice. Exceptions are 25% of invoices, yet their extra handling alone is about 23% of the cost. Approver time alone is 22%. A project that only speeds up keying would leave most of the cost in place.
- Cost per invoice today
- $13.67
- After, before running cost
- $6.64
- Each $1,000 / month of running cost adds
- $0.50
Today
- AP processing
- = 2,000 × 6 min ÷ 60 × $40
- $8,000
- Exceptions
- = 500 × 19 extra min ÷ 60 × $40
- $6,333
- Approvers
- = 2,000 × 3 min ÷ 60 × $60
- $6,000
- Other costs
- = $1,000 rework + $1,200 late fees + $2,500 software + $800 fees + $1,500 overhead
- $7,000
- Cost per invoice
- = $27,333 ÷ 2,000 invoices
- $13.67
After automation, with the default assumptions
- AP review
- = 680 assisted × 1.5 min ÷ 60 × $40 + 10 h oversight × $40
- $1,080
- Exceptions
- = 300 × 18 min ÷ 60 × $40
- $3,600
- Approvers
- = 2,000 × 1.5 min ÷ 60 × $60
- $3,000
- Other costs
- = $400 rework + $400 late fees + $2,500 software + $800 fees + $1,500 overhead
- $5,600
- Running cost
- = Your quote for the new system (not entered)
- $0
- Cost per invoice
- = $13,280 ÷ 2,000 invoices
- $6.64
The after figure is incomplete until a running cost is added, which is why the calculator leaves that field for your quote. Add it, then take the monthly saving into the ROI calculator to see payback.
Where automation changes invoice processing cost
What moves and what stays with your team, line by line. The split between system and people is the part to check hardest in any proposal.
| Cost line | What automation changes | What stays with people |
|---|---|---|
| AP processing | Capture, keying and PO matching move to the system. A person confirms only the invoices it is unsure about. | Review of low-confidence fields and new suppliers |
| Exceptions | Fewer of them, because matching runs on arrival. The PO, receipt and supplier history are gathered before anyone looks. | Real disputes, missing receipts, price changes nobody agreed |
| Approvers | The request arrives with the PO, receipt and match result attached, so approving takes less digging. | The approval decision itself, within your approval matrix |
| Rework | Duplicate, tax and arithmetic checks run before posting instead of after. | Corrections caused upstream, such as a wrong PO |
| Late fees | Invoices reach approval in days instead of sitting in an inbox. | Payment-run timing and cash decisions |
| Software | A new running cost for the system: software, model usage, hosting and support. | Your ERP and the seats AP still needs |
Scroll sideways to see every column.
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Self-assessment · 12 questions
AI readiness assessment
Twelve questions that score one workflow for automation and tell you what to fix first.
Questions about cost per invoice
How do you calculate cost per invoice?
Add every cost of processing invoices in a month: AP time at a loaded hourly rate, the extra time exceptions take, approver time, rework, late-payment penalties and missed discounts, software, payment fees and a share of overhead. Divide the total by the number of invoices processed that month. Time a real sample of 30 to 50 invoices for the minutes, instead of estimating them in a meeting.
What is a good cost per invoice?
We do not quote an industry average. Published figures vary widely by source and invoice mix, and most do not say what they counted. Your own figure, measured the same way each quarter, is more useful. Look at the split between clean invoices and exceptions, since that tells you what to fix first.
What is included in invoice processing cost?
Staff time for AP clerks, approvers and requesters; exception handling and rework; AP software, OCR tools and ERP seats; bank and payment fees; late-payment penalties and missed early-payment discounts; and a share of overhead. Approver time and exceptions are the two items teams most often leave out.
How does automation reduce cost per invoice?
Capture, coding and PO matching move to the system, and a person reviews only the invoices it is unsure about. Better matching cuts the exception rate. Approvers get the PO, receipt and match result with the request, and validation catches duplicates before posting. The system has its own running cost, which this calculator adds back.
Why is the automation running cost blank?
Because we do not publish prices. Enter the monthly quote you have for software, model usage, hosting and support. Until you do, the after-automation figure leaves the system's cost out, and the result panel says so.
Does invoice automation pay off at low volumes?
Often not. At a few dozen invoices a month, software and maintenance can cost more than the time they save. The calculator shows what every 1,000 a month of running cost adds per invoice at your volume. At 100 invoices a month, that is 10 per invoice.
Find out what your invoices really cost.
A 30-minute call with an engineer. Bring a sample of invoices and your process notes, and leave knowing whether automation would pay back.
What happens next
- 1
Strategy call
We learn how the workflow runs today and what a good outcome would be.
- 2
Workflow audit
We map the process and measure where a system would save the most time.
- 3
Proposal
A written scope, timeline and fixed price for your first system. No obligation to build.