Runs 100% on your phone — your medical data never leaves it

Don't pay a medical bill until the math checks out.

FairBill reads your bill or insurance claim and verifies every line with exact, deterministic math — catching duplicate charges, unbundled codes, payment errors, and prices far above what insurers actually pay.

Free to use · No account required · Works offline

The billing system wasn't built for you

Providers negotiate directly with insurers, and patients see inflated "billed" amounts that insurers never actually pay. Errors slip through because nobody reconciles the math on the patient's side. FairBill is that reconciliation.

Exact-math verification

Every claim line must balance to the cent: allowed = deductible + copay + coinsurance + plan paid. If it doesn't, someone is charging you for the gap — and FairBill shows you exactly where.

Real negotiated rates

Paying cash? FairBill compares your charges against the discounted rates insurers actually pay for the same services — so you can negotiate toward the real price, not the sticker price.

Error detection that's provable

Duplicate billing, unbundled lab panels, upcoded visits, charges on codes that must always be $0 — every flag is verifiable arithmetic, not an AI guess.

Built around how insurance actually works

Import a claim PDF, paste your insurer's claim page, scan a paper bill, or enter codes by hand — FairBill handles the insurance-first reality.

Deductible & out-of-pocket tracker

Every audited claim feeds your year-to-date progress toward your deductible and out-of-pocket maximum. Know instantly whether you should even be paying a bill — or whether your deductible is already met.

Plan-mismatch detection

Tell FairBill your plan's coinsurance rate once. If a claim charges you 20% when your plan says 10%, it's flagged with the exact dollar amount and a ready-made "reprocess this" request.

Dispute letters & deadline tracking

One tap generates a formal dispute letter from your audit findings. Mark it sent, and FairBill tracks the 180-day appeal window and reminds you before it closes.

Private by architecture

The audit engine runs entirely on your phone — bills, claims, and plan details are stored only on your device. An optional cloud AI mode exists, but you choose it per audit.

What an audit looks like

A real pattern from claims data: lab work billed at many times the rate the insurer actually allowed.

ServiceProvider billedInsurer-allowed rateMarkup
General health panel$200.55$29.576.8×
Vitamin D test$306.60$21.7314.1×
Lipid panel$107.10$9.8310.9×
Blood draw$26.25$2.4410.8×
Why this matters if you're uninsured

Cash-pay patients get quoted the "billed" column. FairBill arms you with the "allowed" column — the price the provider already accepts from insurers — as your negotiation anchor.

Audit your next bill before you pay it

FairBill is free on Android. Import a claim PDF or paste your insurer's claim page — you'll have a verified audit in seconds, without your data ever leaving your phone.