Last updated: October 15, 2026
How we verify the numbers on RefillMath comes down to three checks: every price comes from an official source, every price is dated next to the number with a link to that source, and every price is reviewed again on the 10th of each month. This page explains each check, how our calculators use the numbers and what to do if you find one that is wrong.
Table of Contents
How we verify a price: 3 checks
Check 1: An official source
We take prices and program terms from official sources:
- The manufacturer’s own pages for list prices, savings cards and their limits, and the prices and conditions for buying directly from the manufacturer.
- Medicare.gov and the Centers for Medicare & Medicaid Services (CMS) for what Medicare covers and what it costs.
- The U.S. Food and Drug Administration (FDA) for approval status, which can affect whether a plan covers a medicine.
We do not use third-party coupon sites, pharmacy advertising, forums or social media posts as sources. If we cannot find an official source for a figure, we leave the figure out.
Check 2: A date and a link next to the number
- Next to each price you will find the date we last checked it and a link to the official page it comes from.
- When a price depends on a condition, such as having commercial insurance or paying cash, the condition is stated next to the price.
- Our own calculations are labeled as ours. The formula and any assumption we make are shown below the result.
Check 3: A monthly review on the 10th
On the 10th of every month we review every price on the site against its official source. When a manufacturer or Medicare announces a change between reviews, we aim to update the affected pages the same day. Every change in a price or in a program’s terms is recorded, with its date, in our price history. This is how we verify that a figure is still current, not just that it was right once.
How we verify each type of figure
Different numbers come from different official pages. This table shows how we verify each one and where we look.
| Figure | Where we check it |
|---|---|
| List price | The manufacturer’s pricing page |
| Savings card terms and limits | The manufacturer’s savings program page and its full terms |
| Price when buying directly | The manufacturer’s direct-purchase page |
| Medicare coverage and cost | Medicare.gov and CMS |
| Approval status | FDA |
How our calculators work
Our calculators run in your browser. They combine the published figures shown on the same page with the numbers you enter. What you type stays in your browser: the calculators do not send it to us and we do not store it.
A calculator result is an estimate, not a quote. Your real cost can be different because of your plan’s deductible, copay or coinsurance, the pharmacy you use, the limits of each savings program and the terms in force on the day you fill your prescription.
Images
Most images on RefillMath are charts and tables we make ourselves from the figures on the page. Some articles also use one stock photo from Pexels. The Pexels license does not require attribution, so we do not add photo credits. We do not use manufacturer logos, images of people’s bodies or before-and-after photos.
What we do not do
- We do not take money from drug makers, pharmacies, insurers or telehealth companies.
- We do not use affiliate links or publish third-party coupons or discount codes.
- We do not write about doses, side effects or which medicine works better. Those questions belong with your doctor or pharmacist.
Found a mistake?
Tell us through our contact form and choose “Report a price or error”. If we confirm the error, we fix it, and if it meets the criteria on our Corrections page, we list it there with the date.
How we verify: common questions
Why does a price show an older check date?
The date shows when we last confirmed the figure against its source. Between monthly reviews, a figure keeps the date of the review in which it was last confirmed.
Can I check a price myself?
Yes. That is how we verify every figure, and it is why each price links to its official source. Open the link next to the number to see the page it comes from.
Do you use prices from pharmacies or coupon sites?
No. A pharmacy’s price can differ from one store to another, and coupon sites are not official sources. We publish figures from the manufacturer, Medicare, CMS or the FDA.
Does a drug maker pay RefillMath?
No. We do not take money from drug makers, pharmacies, insurers or telehealth companies. How we verify a price does not depend on who makes the medicine.