Mastercard KB Transaction Fee Explained

Puzzled by the MASTERCARD KB TRAN FEE on your monthly processing statement? You’re not alone.

This is just one of the many assessment fees charged by Mastercard that’s assessed every time you process one of their cards.

However, not every processor lists this fee as its own line item on monthly statements (because the fee is so small). It’s actually a good sign if your processor lists this assessment—as it highlights transparency about your charges.

Even if the KB Tran Fee isn’t listed, you’re still paying it (which means your processor is making up for this fee in other areas or by padding your assessments). 

What is the Mastercard KB Tran Fee?

Mastercard’s KB TRAN FEE is short for “Kilobyte Access” and it’s $0.0035 per transaction submitted for settlement. 

If you see this fee listed on your statement, you can just do some quick math to ensure your processor is charging you correctly.

Like interchange rates, assessment fees imposed by the card networks are non-negotiable. So if you’ve never seen this fee on your processing statement, you’re still paying it somewhere else. 

Just know that it may not be on every statement (as many assessments are billed quarterly), and the timing here depends on your processor and statement cycle. 

It’s also important to know that you’ll only see this if you’re on an interchange plus pricing model. Sometimes you can find it on tiered or bundled statements, but it won’t be displayed if you’re on a flat-rate pricing plan. 

Some processors may group all of your Mastercard assessments together as a single line item, which makes it harder to tell if they’re charging the right amount for the KB TRAN FEE.

If you’re unsure, you can always have our team here at Merchant Cost Consulting audit your statements to see if your processor is padding your assessments or overcharging you in any way.