AI and accounting
How to use AI to prepare a supplier bill for review
Use these instructions to prepare an invoice draft, check the amounts and follow up on anything that does not match.
AI tools with document-reading capabilities can extract information from supplier invoices and organize it into a draft for review. A reviewer can then compare the draft with the original invoice, check the calculations and resolve missing or inconsistent information.
We recommend testing this with a document you can check yourself before using the tool for routine work. The instructions below give you a starting point.
What should the AI prepare?
The output should include a structured draft and a list of exceptions. The draft contains information supported by the document. The exception list identifies missing fields, unclear text and differences between the printed amounts and the calculations.
It does not mean the supplier has been verified, the goods have arrived, a tax treatment has been selected, an accounting entry has been posted or a payment has been authorized. Those are separate decisions.
Choose a tool your business has approved for the information involved. Check its data-handling terms and access controls before uploading supplier documents. Do not upload bank credentials or unrelated personal information. Begin with a fictional document if you are still evaluating the tool.
- Step 1
AI preparation
Extract fields and flag missing or inconsistent amounts.
- Step 2
Your review
Compare the source, check duplicates and resolve differences.
- Step 3
Approval
An authorized person follows your approval process.
Example instructions for the AI tool
Read the attached supplier invoice and prepare a draft for human review. Extract supplier name, document reference, document date, currency, item descriptions, quantities, units, unit prices, line amounts, discounts, additional charges, tax shown and total shown. Preserve the source wording and identify the page or section for each value where possible. Recalculate the line amounts and total separately. Flag discrepancies, unclear text and missing fields; do not guess. List any candidate duplicate only if you have authorized access to our existing bills, and explain the match. Otherwise mark duplicate checking as not performed. Do not approve, post, send or pay anything. Return the draft, checks performed and unresolved questions.
Adapt the brief to the actual tool. If it can only read a document, do not expect it to check your purchase orders or existing bills. If it can save drafts, confirm where the draft is saved and who can access it. A response in a chat window is not necessarily a durable bill record.
Example: an invoice total that does not match its line items
For this example, suppose you receive invoice LS-1042 from Lantern Supply, dated 10 June in NGN, with these items:
| Source line | Quantity | Unit price | Calculated amount |
|---|---|---|---|
| Desk lamps | 8 units | ₦12,000 | ₦96,000 |
| Storage sets | 6 units | ₦8,000 | ₦48,000 |
| Delivery | 1 charge | ₦6,000 | ₦6,000 |
| Total of listed amounts | Not applicable | Not applicable | ₦150,000 |
Now suppose the printed total says ₦156,000, with no separate tax line or other charge shown. A useful draft preserves both facts: the source says ₦156,000; the listed amounts add to ₦150,000. The difference is ₦6,000.
The assistant should not invent a tax charge to make the amounts agree, quietly replace the printed total or declare the invoice correct. The next action is to ask the supplier to explain the difference. An absent tax line is not proof that no tax applies.
We would expect the review to preserve the printed total and show the difference separately:
| Review field | Expected entry |
|---|---|
| Source | Lantern Supply, LS-1042, 10 June, NGN |
| Printed total | ₦156,000 |
| Recalculated total | ₦150,000 |
| Unexplained difference | ₦6,000 |
| Duplicate check | Not performed: existing bill records unavailable |
| Next action | Ask supplier for a corrected invoice or explanation |
| Approval and payment | Pending; neither action taken |
Attach or link the original invoice to the review record so another reviewer can check the extracted information.
Review the draft against the original
Open the source beside the draft and check these points:
- Identity: is this the intended supplier, not a similar name or an unexpected change of payment details?
- Reference: do the invoice number and date match? Has this document already been recorded?
- Units: does “6” mean six items, six packs or six cartons?
- Amounts: do quantities, prices, discounts, charges and the printed total reconcile?
- Business evidence: do the purchase order and goods-received record support the bill, where applicable?
- Unknowns: has anything been guessed, silently omitted or treated as approved?
If the tool cannot access existing bills, someone must perform the duplicate check elsewhere. If the goods received differ from the invoice, keep that discrepancy open. Neither a complete extraction nor correct arithmetic resolves those business questions.
Approval, permissions and record keeping
Once the reviewer is satisfied, follow your normal approval process. Save the source, the reviewed draft, any corrections and who made the decision. If the software supports separate permissions for preparation, approval and payment, configure and test them; a sentence in a prompt is not an access-control system.
Measure the first exercise simply: which fields were correct, which needed correction, what was missed and whether another person can follow the evidence. Do not measure success only by how quickly an answer appeared.
Evaluating the results
Test the process with a document whose contents you can verify. Record extraction errors, missed discrepancies and any fields that required correction. Check whether a second reviewer can find the source and understand the unresolved items. These results help determine whether the tool is suitable for the task and what review steps are still needed.