I'm trying to save some custom member fields to EE's member section using CartThrob's checkout form.

I have created all the necessary member fields and mapped some of the basic fields in CartThrob's settings and they save just fine. Only the custom_data inputs don't save in the newly created EE member.

Here's the gist of what my form looks like so far:

{exp:cartthrob:checkout_form create_user="yes" group_id="5"}    
    <input type="text" name="first_name" value="" id="first_name" class="required"  />
    <input type="text" name="last_name" value="" id="last_name" class="required"  />
    <input type="text" value="" placeholder="Preferred Name" name="custom_data[preferred_name]" />
    <input type="text" value="" placeholder="DOB Day" name="custom_data[member_dob_day]" />

This was all done following CartThrob's docs and many iterations of not working. Any direction guys, much appreciated.

2 Answers 2


You might find this post useful which shows how we approached this scenario.

Cartthrob checkout form with different billing and member information


I believe the id is missing in your custom_data inputs.

Try it like this:

<input name="custom_data[whatever]" id="custom_data[whatever]" />

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.