Martial arts school staff helping a parent update payment information.

Understanding Credit Card Payments Response Codes within Black Belt Membership Software

At Black Belt Membership, we know your cash flow is the backbone of your school. That’s why we’ve partnered with NMI, one of the most trusted payment gateways in the industry. NMI powers secure, reliable transactions for thousands of businesses, and martial arts schools are no exception.

But every gateway speaks its own “language.” With NMI, that language is response codes. These short numeric codes explain what happened during a payment attempt. Most of the time, it’s smooth sailing. But when something does go wrong, these codes tell you what to do next.

To save you time, we’ve put together this easy guide. Below you’ll find the most common codes you’ll see in Black Belt Membership, along with what they mean and how to respond.


Black Belt Membership Payment  Response Codes at a Glance

Here’s a simplified table with the codes most relevant to martial arts school owners.

Code Meaning What to Do
100 Approved No action needed. Payment went through.
200 Declined by processor Politely ask member to confirm card details or try a different card.
201 Do not honor Ask the member to call their bank for approval.
202 Insufficient funds Retry later or request another card.
223 Expired card Ask member for updated card details.
225 Invalid CVV Confirm the security code on the back of the card.
261 / 262 Stop recurring payments Contact member directly. Respect request and update their billing.
263 Update cardholder data available Use NMI’s card updater or ask for new details.
300 Rejected by gateway Retry once; if it repeats, contact support.
410 / 411 Invalid merchant setup / inactive account Reach out to Black Belt Membership or NMI support.
420 / 421 Communication error Wait and retry. Often temporary.
430 Duplicate transaction Double-check before re-running charges.
461 Unsupported card type Ask for a different card (Visa, MasterCard, etc.).

For a full list and official details of all NMI Gateway Response Codes, visit NMI Response Codes Documentation.

How to Use This Table in Your School

The table above isn’t meant to overwhelm you. It’s a quick reference so you don’t waste time guessing. Here’s how you can make it work:

  1. Keep it handy — print it out and post it near your front desk or office.

  2. Train your team — make sure staff know how to spot these codes in Black Belt Membership.

  3. Respond consistently — when a decline happens, follow the same steps every time. It builds trust with families.

Best Practices for Handling Declines

  • Be proactive: Don’t wait until tuition stacks up unpaid. Use Black Belt Membership’s alerts to act quickly.

  • Communicate politely: A short text or email goes a long way. Most families simply need a reminder.

  • Retry smartly: Try again 24–48 hours later. Avoid multiple same-day attempts.

  • Stay professional: Declines happen. It’s rarely personal. Focus on solving, not blaming.

Black Belt Membership uses NMI because it’s reliable, secure, and trusted. But even the best gateway will occasionally return a decline or error. By understanding these response codes, you can respond quickly, recover payments, and keep your school’s finances healthy.

Want to see how Black Belt Membership makes billing and collections easier with NMI?

 or set up your account today. We’ll walk you through the setup, show you how to read codes, and help you keep tuition flowing smoothly.

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