https://community.developer.cybersource.com/t5/Integration-and-Testing/20-character-limit-on-merchantCustomerId/m-p/65897#M39501 The solution to that for a quick fix is to use a field other than customer id. You can pass the value under anything and then call it customer id on your end. You can also put in a request in the suggestions forum. I don’t think there is a way to customize the API however. You could alter the files on your end but they’re still going to get kicked back on the API call. Sat, 19 Jan 2019 11:45:29 GMT Renaissance 2019-01-19T11:45:29Z https://community.developer.cybersource.com/t5/Integration-and-Testing/20-character-limit-on-merchantCustomerId/m-p/65889#M39495 <P>I am new to this platform, but am already concerned with a number of properties that have a limit of 20 characters.</P><P>In particular, properties that are sourced from the integrator.</P><P>Is there any possibility of increasing the length of fields that are reference values from an integrator to at least 36 characters?&nbsp;</P> Fri, 18 Jan 2019 19:33:12 GMT https://community.developer.cybersource.com/t5/Integration-and-Testing/20-character-limit-on-merchantCustomerId/m-p/65889#M39495 aaronhudon 2019-01-18T19:33:12Z https://community.developer.cybersource.com/t5/Integration-and-Testing/20-character-limit-on-merchantCustomerId/m-p/65897#M39501 The solution to that for a quick fix is to use a field other than customer id. You can pass the value under anything and then call it customer id on your end. You can also put in a request in the suggestions forum. I don’t think there is a way to customize the API however. You could alter the files on your end but they’re still going to get kicked back on the API call. Sat, 19 Jan 2019 11:45:29 GMT https://community.developer.cybersource.com/t5/Integration-and-Testing/20-character-limit-on-merchantCustomerId/m-p/65897#M39501 Renaissance 2019-01-19T11:45:29Z