In your Procore & Xero Integration, in the Settings page, there is a tab for Defaults, where you will set up your default payment terms, as well as the default Xero Account Codes that Procore will sync to in case of there being no mapped account, the retention account codes used (if you are using retentions, see this article for more detail). You can also set up the Procore Cost Codes that Xero will assign to in case there is no existing mapping if you wish to do so.
Contact Payment Terms
The Contact Payment Terms can be set here, you can type the number you wish to be set as well as choose what it will be applied to in the dropdown.
The contact payment terms can be selected as an option for the payment terms for Direct Costs, Commitments (AU/UK/NZ)/ Requisition (US/CAN), and Head Contract (AU/NZ) / Prime Contract (USA/CAN) / Main Contract (UK).
Xero Account Codes
In the Xero Account Codes section of the Defaults page you set the account codes that invoices or bills that the integration will push across to in the case that there is no Procore cost code <->Xero account code mapping (i.e. fallback codes).
The invoice code will be the income code and the bills will be the expense codes.
Retention Codes
This is where you set the retention codes for commitments and head contract:
For information on how to set retention codes, see this article.
Procore Account Codes
The invoice code and bill code will be the default cost codes a Xero invoice or bill will be sent to in the case that there is no existing mapping for that account code. It is not required unless you want all Xero invoices or bills for that project to appear in Procore, in the case that you do you can set the Procore cost codes here:
