The numbers most bookkeepers don't track
Bookkeepers know that manual invoice entry is slow. But few actually calculate what it costs them across all their clients each month. When you do the maths, the numbers are hard to ignore.
Time per invoice
Based on industry averages and our own observations, manual invoice entry takes:
- Simple invoice (1-2 line items): 2-3 minutes
- Standard invoice (3-5 line items): 4-5 minutes
- Complex invoice (6+ line items, mixed VAT): 6-8 minutes
This includes opening the PDF, reading the details, typing them into the accounting software, and double-checking the amounts.
Scaling across clients
Here's where it adds up. Say you manage bookkeeping for 8 clients, and each client has an average of 25 invoices per month:
| Per client | All 8 clients | |
|---|---|---|
| Invoices per month | 25 | 200 |
| Time at 4 min each | 100 min | 800 min |
| Hours per month | 1.7 hrs | 13.3 hrs |
That's over 13 hours a month just typing invoice data. At a typical bookkeeping rate of £30-40/hour, you're either absorbing £400-530 of unbillable time, or charging clients for work that adds no value.
The error cost
Time is only half the problem. Manual entry introduces errors:
- Transposed digits: £1,450 becomes £1,540
- Wrong dates: Invoice dated January gets entered as February
- Missing line items: A 5-line invoice gets entered as 4 lines
- VAT mistakes: Standard rate applied to zero-rated items
These errors surface during bank reconciliation or VAT returns, and fixing them takes additional time. Studies on manual data entry suggest an error rate of around 1-2% of fields, which for 200 invoices with 6 fields each means roughly 12-24 corrections per month.
What automation actually saves
Using a tool like InvoiceCSV, the conversion step drops from 4 minutes per invoice to about 30 seconds (upload, review, download). For 200 invoices:
| Manual | With InvoiceCSV | |
|---|---|---|
| Time per invoice | 4 min | 0.5 min |
| Total time | 800 min (13.3 hrs) | 100 min (1.7 hrs) |
| Time saved | - | 700 min (11.7 hrs) |
| Cost saved (at £35/hr) | - | £409/month |
The Starter plan costs £19/month and covers 200 invoices. That's a return of roughly 20x on the subscription cost.
Beyond the direct savings
Faster invoice processing also means:
- Faster month-end close: Clients get their books done sooner
- Fewer queries: Less time chasing corrections and mismatches
- More capacity: Take on additional clients without hiring
- Better accuracy: Fewer errors means fewer problems at VAT return time
The real question
If you're spending 13+ hours a month on invoice data entry, what else could you do with that time? Take on two more clients? Offer advisory services? Finish work on Friday afternoon instead of Saturday morning?
The maths is straightforward. Manual entry at scale is one of the most expensive things a bookkeeping practice does, and one of the easiest to fix.
Try InvoiceCSV free - 5 conversions per month, no card required.