Understanding payment rates: Your complete guide

While fees are important, they are only half of the story. The other half is your payment acceptance rate, the percentage of attempted payments that actually end up in your bank account.

These are the four most important metrics you need to consider:

1. Authentication rate

Verifies that the person paying is the legitimate owner via 3D Secure (3DS). 

The authentication rate measures the effectiveness of the 3DS authentication process: the higher it is, the more confident you can be that the transactions on your site are legitimate. A high authentication rate prevents fraudulent attempts while enabling secure payments.

How to calculate authentication rate: Divide the number of successfully authenticated payments by the total number of payments that required authentication.

(Successful 3DS Authentications ÷ Total 3DS Attempts) x 100

What it means: A high authentication rate means your security is working smoothly, stopping fraudsters without blocking real customers.

2. Payment authorisation rate

Once a customer is authenticated, the transaction is routed to the card networks (such as Visa or Mastercard). The payment authorisation rate is the proportion of transactions these networks actually approve.

Your payment service provider (PSP) acts as the messenger here, sending data to the bank and bringing back a ‘yes’ or ‘no.’ 

How to calculate authorisation rate: Divide the number of transactions approved by the card networks by the total number of transactions submitted to those networks (the ones that passed or skipped the 3DS step).

(Approved Transactions ÷ Total Transactions Submitted to Networks) x 100

What it means: A high authorisation rate indicates that your transactions are trusted by banks, resulting in a seamless experience for your buyers.

3. Conversion rate

This is the ultimate indicator of your business performance. It reflects the proportion of successful payments compared to every single attempt made on your site.

Unlike other rates, the conversion rate accounts for everything: security checks, technical errors, and even the moments a customer hesitates and lets their session expire. 

How to calculate conversion rate: Divide the total number of successful payments by the total number of payment requests (every time a customer clicks pay).

(Successful Payments ÷ Total Payment Requests) x 100

What it means: A high conversion rate means that you’ve built a checkout experience that has removed the friction that loses sales, ensuring visitors are more likely to make a purchase.

4. Acceptance rate

The payment acceptance rate focuses on the final outcome for each unique customer. It measures whether a buyer ultimately completed their purchase, regardless of how many tries it took.

For example, if a customer’s first card is declined but they immediately succeed using a different card or a Buy Now, Pay Later option like Klarna, it counts as a 100% success for that user. 

How to calculate acceptance rate: Divide the number of unique customers who successfully completed a purchase by the total number of unique customers who attempted to pay.

(Successful Unique Customers ÷ Total Unique Customers Who Attempted to Pay) x 100

What it means: This is a great metric for measuring overall business growth and customer satisfaction.

Comparing acceptance rate vs conversion rate

The key difference lies in the journey. The acceptance rate shows you the destination (did they eventually pay?), while the conversion rate reflects the buyer journey (how easy was it?).

If you have a high acceptance rate but a low conversion rate, it’s a signal worth investigating. It could mean your customers are persistent, but they are struggling with declines or glitches before finally getting through. 

Monitoring both allows you to see not only that you’re getting paid, but also how easily your customers can pay you.