How to Calculate Your True Chargeback Ratio

To calculate your chargeback ratio, divide your chargebacks in a month by your transactions in that month and multiply by 100. Nine chargebacks on 1,000 transactions is 0.9%. That's the arithmetic everyone quotes, and it's the number your processor probably isn't using.

There isn't one chargeback ratio. There are several, they use different inputs, and they give different answers for the same month of trading.

Three Different Numbers, Same Business#

Here's why your figure and your processor's figure disagree.

Your simple ratio counts chargebacks against transactions. It's useful for tracking your own trend and nothing else.

Visa's VAMP ratio is a different measure entirely. It combines fraud and disputes, and it only looks at card-absent volume.

Your acquirer's internal limit is a third number, usually stricter than the network's, and it's the one that actually gets your account held.

Most merchants track the first and get surprised by the third.

What Visa Actually Measures#

Since 1 June 2025, VAMP replaced Visa's separate fraud and dispute monitoring programs with one measure (Visa).

The formula is count-based, not value-based:

VAMP ratio = count of fraud (TC40) plus disputes (TC15), divided by count of settled transactions (TC05)

Four things about that differ from the simple calculation:

• It adds fraud to disputes. A month with low chargebacks but high reported fraud can still push you up.
• It counts transactions, not dollars. A $12 dispute weighs the same as a $1,200 one.
• It covers card-not-present volume. Card-present sales don't enter the ratio the way most merchants assume.
• It excludes two things. Disputes resolved through pre-dispute solutions drop out, and so does fraud that qualified for Compelling Evidence 3.0.

That last point is the one worth acting on. Refunding through an alert before a dispute is formally filed doesn't just avoid a chargeback, it keeps the event out of the ratio.

The Thresholds, and the Part Everyone Omits#

Visa publishes the numbers, and they come in pairs.

An acquirer's portfolio is identified as Above Standard at 50 basis points and Excessive at 70. Those are the acquirer's, not yours, but they explain why your processor panics at levels that look fine to you.

For merchants in the US, the Excessive threshold is 150 basis points and 1,500 or more fraud and dispute events in the month. Both conditions have to be met. That US ratio dropped from 220 basis points on 1 April 2026.

The count floor is the part nearly every guide leaves out, and it changes the picture completely. A shop doing 1,000 transactions a month cannot reach 1,500 events. It will never be identified as an Excessive Merchant on ratio alone. It can still be terminated by its acquirer, which is the real risk.

Our VAMP calculator applies both tests, and the chargeback ratio calculator handles the simple version.

Work Through a Real Month#

Say you process 4,000 card-not-present transactions, take 38 disputes, and the issuers report 14 fraud transactions.

Simple ratio: 38 divided by 4,000 is 0.95%.

VAMP ratio: 38 plus 14, divided by 4,000, is 1.30%.

Now suppose 9 of those disputes were resolved through pre-dispute alerts. Those drop out, giving 29 plus 14 over 4,000, or 1.08%.

Same month. Three defensible numbers between 0.95% and 1.30%, depending on which rules you apply. When your processor quotes a figure, ask which one they mean.

Getting the Denominator Right#

The numerator gets the attention, but the base is where the quiet errors live.

Count settled transactions, not authorizations. Declines and abandoned authorizations aren't sales, and including them flatters your ratio.

Use the same period for both halves. Mixing this month's disputes with last month's volume produces a number that means nothing, though be aware programs and acquirers differ on which month's base they apply, so confirm what yours uses rather than assuming.

Don't net out refunds. A refunded sale still settled. If refunds are your concern, that's a separate measure, and our refund ratio calculator covers it.

Count each dispute once. A dispute that escalates to pre-arbitration is still one event.

Why Your Ratio Moves Without You Changing Anything#

Three mechanical causes, none of them about your product.

Volume drops. The denominator shrinks faster than disputes do, so a slow month raises the ratio on its own. Seasonal businesses get caught by this constantly.

Timing. Disputes arrive weeks or months after the sale. A great month for sales shows its disputes later, so growth flatters the ratio now and punishes it afterwards.

Mix. Shifting toward card-absent sales moves volume into the measure VAMP actually counts. We covered that gap in card present versus card not present.

What to Do With the Number#

Track it monthly, not quarterly, since the programs are monthly and a quarterly average hides the month that triggers a review.

Track fraud separately from disputes even though VAMP combines them, because the fixes differ. Fraud responds to 3-D Secure, address and card verification, and velocity limits. Disputes respond to clear descriptors, responsive support, and easy cancellation.

Watch the trend line rather than the single reading. Three months climbing matters more than one bad month.

And ask your acquirer directly what limit applies to your account and which formula produces it. That question gets a straight answer more often than merchants expect, and it's the only threshold that can actually close you down. If yours is already high, chargeback defense and representment are where to start.