When you import or enrich a contact or a company that already exists in lemlist, the incoming data can target a field that already holds a value. With Field updates, an admin sets one rule per source that decides what happens in that case: keep the value you have, replace it, or add the new value next to it. The rule applies to the whole team, so every import from the same source behaves the same way and values your team corrected by hand are not lost on the next import.
Limitations
Field updates is in beta and is enabled team by team. If your team doesn't have it, every import keeps its previous behavior and the CSV import keeps the Don't overwrite checkbox on each column.
Only team admins see the Field updates tab.
Rules apply to the whole team. You cannot set a different rule for a single import.
Rules are not retroactive. Changing a rule doesn't change records already in lemlist.
Field updates doesn't apply to manual edits, duplicate merges, or fields computed by lemlist.
CRM imports are not managed in Field updates. Your CRM field mapping decides what is written.
The API doesn't follow Field updates. It uses its own
updateStrategyparameter on each request, which overwrites by default.Company enrichment and Verify email have no setting.
How a rule is applied
lemlist first checks if the incoming contact or company already exists, using the matching criteria set in Settings → Data management → Duplicates (email, LinkedIn URL, Sales Navigator URL, company domain).
If it exists, the Field updates rule of the source decides what happens to each field that already holds a value.
A column or key you don't send is never modified, whatever the rule.
Phase 1: Open Field updates
Go to Settings → Data management → Field updates.
✅ Verify: the page lists the import sources and the enrichment types, each with its own rule.
Phase 2: Set the rule for each import source
Sources: People database, LinkedIn extension, CSV import, Signal agents. Each has three options:
Fill empty fields only: a value you already have is never changed. Empty fields get filled.
Overwrite: incoming data replaces what you have. Blank cells are ignored.
Overwrite also with empty value: a blank cell in a mapped column clears the field. This is the only option that can delete data.
Defaults:
CSV import: Overwrite (blank cells ignored)
People database, LinkedIn extension, Signal agents: Fill empty fields only
Select the option you want on the row of a source. Each row saves on its own.
✅ Verify: the row shows the option you selected.
CRM import is not set on this page. Click the button on the CRM row to open your CRM settings, where the field mapping decides what is written.
Phase 3: Set the rule for each enrichment type
Email enrichment and Phone enrichment:
Create a new field (default): the found value is added next to the existing one. Nothing is replaced.
Write in the existing field: the found value replaces the existing one.
LinkedIn enrichment:
Fill empty fields only (default)
Write in the existing field
An empty result never erases anything.
Company enrichment has no setting: it fills empty fields only.
Verify email has no setting: it always refreshes the status.
With Create a new field, Phone enrichment fills the empty phone columns first and creates a new one when they are all full. It no longer clears the phone columns before writing.
A forced enrichment (Search all) still pays the scan. The rule decides what is written.
Phase 4: Check who changed a rule
Go to Settings → Logs.
✅ Verify: each rule change shows who changed it, when, the source, the previous rule and the new rule.
What changes in the CSV import
At the mapping step, a sentence says that existing values follow the team's Field updates rules.
Admins also see an Open Field updates shortcut. Members see the sentence only.
The Don't overwrite checkbox on each column is removed. The CSV import rule replaces it.
What changes when your team gets Field updates
With the default rules:
A blank CSV cell no longer erases a value. It did before.
A LinkedIn extension or People database push onto a known contact now fills its empty fields. Before, the contact was left untouched.
Pushing a known contact to a campaign never rewrites the contact. The contact is the source of truth and the lead copies it.
Practical example
Your team wants to refresh job titles from a trusted CSV export without losing the phone numbers enrichment found. An admin keeps CSV import on Overwrite. The rep exports a file with the email and job title columns only and imports it. Job titles are replaced. Phone numbers are not modified because the file doesn't send a phone column.
To make sure a provider never replaces a value your team typed, the admin sets LinkedIn enrichment to Fill empty fields only and keeps Email enrichment and Phone enrichment on Create a new field. Enrichment then completes the gaps only.
Troubleshooting & pitfalls
Issue: I don't see the Field updates tab
Root cause: You are not a team admin, or Field updates is not enabled for your team.
Fix:
Ask a team admin to open Settings → Data management → Field updates.
If no admin sees the tab, your team doesn't have the beta. Imports keep their previous behavior.
Issue: A blank cell in my CSV cleared a value
Root cause: The CSV import rule is Overwrite also with empty value.
Fix:
Change the CSV import rule to Overwrite or Fill empty fields only.
Import the file again with the missing values filled. Changing the rule doesn't restore cleared values.
Issue: A re-import didn't update existing values
Root cause: The source is on Fill empty fields only (the default for People database, LinkedIn extension and Signal agents), or the incoming record didn't match the existing one.
Fix:
Set the source to Overwrite if you want incoming values to replace existing ones.
Check the matching criteria in Settings → Data management → Duplicates.
Issue: The Don't overwrite checkbox is gone from the CSV import
Root cause: Your team has Field updates. The CSV import rule replaces the checkbox.
Fix: Set the behavior you want on the CSV import row in Field updates, or ask a team admin to do it.
If your case is different
If you want to set contact or company owners from a CSV, see Assign contact and company owners from a CSV import.
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 merge existing duplicates, see Merge duplicate contacts and companies in bulk.
If you want to control what a HubSpot sync writes, see Map fields for the HubSpot integration. For Salesforce, see How to configure field and user mapping in Salesforce.
If you want to change which enrichment providers run first, see Choose which enrichment providers run first with a custom waterfall.