AI Bill & Invoice Analysis: Understand Charges and Spot Anomalies (2026)
Bills are rarely hard because the total is large. They’re hard because the breakdown is messy: codes, tiny fonts, line items, “adjustments,” and hidden fees.
This post gives a repeatable workflow to:
- extract the important fields
- compare month-to-month changes
- flag suspicious line items
- export data for reimbursement/accounting
The 5 goals
- total due + due date
- line-item breakdown
- compare with last period
- hidden fee / penalty check
- export to CSV
5-minute workflow
Step 1: Capture the smallest useful sections
Include header + totals + the line-item table.
Step 2: Extract fields as a table
Ask for:
vendor/provider
invoice/bill number
period
subtotal/tax/discount/total
line items (qty/unit price/amount)
Step 3: Compare with last month
Ask:
- “What changed vs last month? Rank changes by dollar impact.”
- “Any new items? Any discounts expired?”
Step 4: Hidden fees and terms
Ask:
- “List all service fees/adjustments and explain them.”
- “Any late fees, minimum charges, auto-renew notices?”
Step 5: Export template
Request a CSV with:
- date, vendor, invoice #, category, tax, amount, notes
Bottom line
Turn bills into data, compare, and act.