You can set the owner of each contact and company from your CSV file. Add a column with a teammate's email (for example "Contact owner"), map it to Owner, and each row gets that teammate as owner. This works for new records and for records you already have in lemlist, so you can also reassign owners in bulk.
Owner columns work in three imports:
Contacts CSV import: sets the contact's owner and the owner of its company.
Companies CSV import: sets the company's owner.
Campaign CSV import (Leads list › Import new leads › CSV import): sets the owner of the contact and of its company. The lead itself has no owner.
Limitations
Only emails of members of your lemlist team can be set as owner.
Only English headers are detected automatically (headers containing "owner", "company" or "account"). Columns with other headers must be mapped to Owner by hand.
Automatic detection reads the first five rows of a column. If the column is empty on those rows, map it by hand.
A company owner on a contact row without company columns is ignored.
The watch-list CSV import does not support owner columns.
A row where only the owner changes is counted as "unchanged" in the import summary.
How each owner cell is read
Email of a teammate (in any letter case): that teammate becomes the owner.
Empty cell: a new record is created with no owner. On an existing record, the owner is removed, unless the column is protected (see Phase 3).
Anything else (an email outside your team, a name, a typo): a new record gets you, the person importing, as owner. An existing record keeps its current owner.
No owner column: the import works as before.
Phase 1: Prepare your CSV
Add a column with the owner's email on each row. Use a header that names an owner so it is detected automatically:
"Contact owner" or "Owner email" set the contact's owner.
"Company owner" or "Account Owner" set the company's owner.
Use the email each teammate uses in lemlist.
The "owner" column of a lemlist contacts export contains names, not emails. If you re-import an export, that column is not mapped to Owner.
Phase 2: Map the owner columns
Start a CSV import from Contacts, Companies, or a campaign's Leads list, and upload your file.
At the mapping step, check the owner columns. Columns detected as owner columns are already mapped to Owner. In a contacts or campaign import, Owner appears twice in the dropdown: under Contact fields (the contact's owner) and under Company fields (the company's owner).
To map a column by hand, open its dropdown and select Owner under the right section.
✅ Verify: "Contact owner" is mapped to Owner with a person icon and "Company owner" to Owner with a building icon.
Click Continue.
Phase 3: Check unknown owners and protect existing owners
If some cells hold emails that are not in your team, a blue message appears on the last step of a Contacts or Companies import, and on the settings step of a campaign import:
Some emails in "Contact owner" and "Company owner" do not belong to the lemlist team; the owner of the new contacts and companies will be defined as the user who imported them into lemlist, and existing ones keep their current owner.
With one owner column, the message names that column only. To fix it, correct the emails in your file and upload it again.
Decide what empty owner cells should do to existing records:
To keep the current owner of existing records, check Don't overwrite on the owner column.
If you don't see a Don't overwrite checkbox, your team's Field updates rule for CSV imports applies to the owner column: Overwrite and Fill empty fields only keep the current owner on an empty cell, Overwrite also with empty value removes it.
Complete the import.
✅ Verify: open a few imported contacts and companies and check the Owner field.
What happens after the import
For records linked to your CRM, the new owner is pushed to the CRM.
Campaigns that use Contact owner as sender strategy use the new owner as sender. See How to use Dynamic Senders in a campaign.
The lemlist MCP CSV import tools support owner columns too. In the campaign import tool, map the owner columns explicitly in the column mapping.
Practical example
Your sales manager splits 500 accounts between two reps. She exports the list, adds a "Contact owner" column and a "Company owner" column with each rep's email, and imports the file into Contacts. Existing contacts and companies are reassigned to the right rep, new ones are created with that rep as owner, and the rep's campaigns that send from the contact owner pick them up.
Troubleshooting & pitfalls
Issue: An owner column was not detected
Root cause: The header is not in English, does not name an owner, or the first five rows are empty.
Fix:
At the mapping step, open the column's dropdown and select Owner manually.
Or rename the header, for example to "Contact owner", and upload again.
Issue: Existing contacts lost their owner
Root cause: The owner cells were empty and the column was not protected.
Fix:
Fill the owner cells and import the file again, or reassign the owner from Contacts (select contacts › More › Change owner).
Next time, check Don't overwrite on the owner column, or keep your Field updates rule on Overwrite or Fill empty fields only.
Issue: An owner column became Owner instead of a campaign variable
Root cause: In the campaign CSV import, a column whose header names an owner and whose cells hold emails is mapped to Owner automatically.
Fix: At the mapping step, remap the column by hand to keep it as a variable.
Issue: Contacts were assigned to me instead of my teammate
Root cause: The email in the file is not the email your teammate uses in lemlist, so new records went to you.
Fix: Correct the email and reassign the contacts from Contacts (select contacts › More › Change owner).
If your case is different
If you want to change the owner of contacts already in lemlist without a file, see Use the Contacts section.
If you need help with the rest of a campaign CSV import, see How to import leads from a CSV file.
If you want to import companies, see Companies section: overview.