Merge a Marketo Field with a SFDC Field – Deep Dive

Marketo Employee
Marketo Employee

Merging fields is a trick Marketo support and services can do to combine a Marketo only field with a SFDC field.





Marketo won’t be able to merge a field if the type doesn’t match the field you are merging with. Thus, they can only merge a string field with a string field. They won’t be able to merge a date with a datetime field.



They won’t be able to merge a field if it is in use.



Merging fields starts with selecting which field (Friendly name will remain).



When they merge fields you need to determine which field you are merging with, it is called this the Target Field. Target is the field which will remain after the merge. You also need to choose which value will win.



Merging fields may take some time and once started it cannot be canceled. Once the merge is completed the merged field will no longer exist in Marketo.



Important: If you are in the process of integrating/syncing SFDC with Marketo for the first time, I highly recommend you merge the fields before you start the record sync between SFDC and Marketo. Since merging fields takes time I recommend building this task into your implementation schedule.



Checklist of information to provide Marketo professional services.

  • Names of the fields to be merged.
  • Confirm the two merged fields are of the same field type
  • Confirm all the fields to be merged are not being using in any smart lists/campaigns
  • Determine which value will win for each merge



Additional resources for learning about the Marketo integration with SFDC.

Level 4

Hi Brian Law​,

I just ran across this post while working with Marketo support on a field merge we wished to complete. I was told by my support rep that not only does the type have to be the same (string, boolean, etc.) but standard and custom fields cannot be merged. The use case here was that we wanted to merge a custom Global Unsubscribe field with the standard Unsubscribed field. Could you please verify that this is correct? I think it's an important detail to consider if someone is looking to merge fields.


Level 10

Hi Bonnie,

Yes, this is correct, AFAIK.


Level 4 - Champion

Hey Bonnie Jeffers

We thought that as well, however, support was able to "remap" the standard Lead Status Field on the lead with a custom Lead Status field on the contact into Marketo's Person Status field.  The process definitely took longer and it requires you to turn off your Marketo <=> SFDC Sync, but they were able to do it for us. Unsubscribe might be different though because it is a system field and I bet there are restrictions on that field. Below are the steps we got from support prior to the remap.  Hopefully this helps get you what you need!


From Support:

I attempted to merge the fields and was unable to as our merging tool currently only allows merging custom fields. We cannot merge a custom field (i.e. Lead Status (C) ) into a standard field (i.e. Person Status) at this point in time.

Alternatively, I can perform a field remap so that the Person Status field in Marketo also points to the FCRM__FCR_Status__c Contact field in SFDC. In order to do this, it is recommended to:

  1. Perform a backup on the Person Status field as a precautionary step. This could be done by creating a smart list in Marketo to find all records where Person Status is not empty, create a custom view including SFDC ID, Email Address and Person Status field, and then export the data

Once the backup is completed, please let me know and I can proceed with the following:

  1. Temporarily disable global Salesforce sync
  2. Perform field remap
  3. Re-enable global Salesforce sync
  4. Delete the Lead Status (C) field
Level 4

Thanks, Kyle. I am working on something similar with Marketo Support now. Apparently, there were some non-standard mappings done between this MTKO instance and SFDC. This instance has been around for quite a few years, too.

I'm not sure why, but that link you posted is restricted to me. But I am creating a backup of my Unsubscribe data to be safe. I appreciate your input.