---
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"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/64023#article
headline: "64023: Pay: Invalid Test Bank Account Number"
url: https://www.twilio.com/docs/api/errors/64023
inLanguage: en
dateModified: 2026-03-11T22:03:37.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 64023: Pay: Invalid Test Bank Account Number

Log Type: APPLICATION

Log Level: ERROR

## Description

A 64023 error is an indication that your Pay Connector is in TEST mode, but you did not provide a valid test bank account number when testing an ACH payment.

### Possible causes

* Your pay connector is in TEST mode and you provided an invalid test bank account number when testing an ACH payment. For compliance reasons, we can only allow certain test bank account numbers in TEST mode.

### Possible solutions

* Check the documentation for the pay connector in the Twilio Console or in our Twilio docs for valid bank account numbers that can be used when in TEST mode.