A row needs at least one parseable phone number or it’s rejected.
Additional phones
Extra phone columns in your CSV
No
Merged onto the same lead and deduplicated.
Time zone
The column you map as Timezone column header
No
Falls back to the campaign’s default time zone when blank or unmapped. Used to evaluate calling-hours windows.
Attributes
Any other column in your CSV
No
Every unmapped column becomes a free-form text attribute on the lead, using the column’s own header as the attribute name. Available to agent scripts as tokens.