A working Excel/Sheets template with carrier-invoice columns, enrollment cross-reference, and variance formulas. Free. No email required.
Also: the math on why every HR team using a spreadsheet like this one loses about $60,000 per year to billing errors they never find.
From the carrier invoice. Exactly as billed.
EE, EE+SP, EE+CH, FAM.
MED, DEN, VIS, LIFE, STD, LTD.
Dollar amount the carrier charged for this person-line.
What your enrollment system says they should owe — use VLOOKUP from a second sheet.
=D-E. Highlight red if the absolute variance is > $1.
That's the whole method. You populate columns A–D from the carrier invoice (paste, or re-type, or if your carrier's PDF is locked, re-type twice to check). You populate column E from your enrollment system export. Column F reconciles the two.
Retro adjustments.Carrier retro-terms a member mid-cycle and back-adjusts three months of billing into one line. Your variance formula flags it. Your formula doesn't tell you which three months.
Tier mismatches. Invoice says EE+SP, enrollment says FAM. Variance looks small. It compounds over every month until someone catches it.
Terminated-still-billed.The member isn't in your enrollment export at all. VLOOKUP returns #N/A. You filter it out and forget.
Duplicate billing across invoices.Carrier sends two invoices in the same cycle. Different invoice numbers. Same member. Your spreadsheet doesn't know about the other file.
ERISA audit-trail requirements. If your plan is ever audited, you need a tamper-evident ledger showing when each discrepancy was identified, disputed, and resolved. A spreadsheet is not that.
Form 5500 Schedule H totals. Your accountant needs carrier-by-carrier plan-year rollups, not a VLOOKUP. Pulling that out of twelve monthly sheets is a half-day every April.
Industry baseline: ~5% of monthly premium spend is in error. The source is AdminaHealth's multi-year dataset and Beneration's published case studies — the range holds across fully-insured books of most sizes.
| Your monthly premium | 5% in error | Per year | A spreadsheet catches ~1% | You're leaving behind |
|---|---|---|---|---|
| $50,000 | $2,500 | $30,000 | $500 | $24,000 |
| $100,000 | $5,000 | $60,000 | $1,000 | $48,000 |
| $200,000 | $10,000 | $120,000 | $2,000 | $96,000 |
| $500,000 | $25,000 | $300,000 | $5,000 | $240,000 |
| $1,000,000 | $50,000 | $600,000 | $10,000 | $480,000 |
The 1% spreadsheet-catch rate is being generous. Most HR teams we've benchmarked against catch 0–0.5% of actual errors — retro adjustments and tier mismatches are the two categories a variance column will almost never surface on its own.
Same carrier invoice. Same enrollment export. Reducto pulls every line, Claude normalizes it against your roster, and the engine flags retro adjustments, tier mismatches, terminated-still-billed, and duplicate billing — priced, ranked, and exportable to Form 5500 Schedule H.