Klaviyo → AcelleMail Migration — Visual Walkthrough

Before you start#

You'll need:

• A Klaviyo account with profile-export permission (Owner or Admin role)
• An AcelleMail installation up and running
• ~45 minutes for <100k profiles + tags + custom properties

Klaviyo's profile model is rich (event history, conditional segments, predictive metrics). The CSV migration preserves identity + custom properties; behavioural segments + flows are rebuilt manually in AcelleMail's visual builder.

Export from Klaviyo#

In Klaviyo's left sidebar, click Audience → Lists & Segments → choose the list to export. On the list page, Manage List → Export List to CSV.

Klaviyo asks which properties to include — select All (or trim down if you have hundreds of custom properties you don't need). The file prepares in the background; Downloads sidebar item shows the download link when ready (usually <5 minutes for <100k).

Exported CSV includes: email, all standard + custom profile properties, opt-in date, source, last activity timestamp.

For segment-based migration (e.g. only profiles matching "Engaged in last 30 days"), use Segments → [segment name] → Export Segment — same flow, scoped output.

Import into AcelleMail (the same 6 clicks for every source)#

Once you have the CSV exported from your previous platform, the import flow in AcelleMail is identical regardless of where the data came from.

1. Open your destination list#

In AcelleMail's sidebar, click Audience → choose the list that will receive the migrated subscribers (or create a new one — New list button top-right).

You'll see a per-list overview card with subscriber counts:

2. Click "Import" in the list toolbar#

The wizard entrypoint is on the list detail page:

3. Upload your CSV#

Drop the CSV file from the previous platform into the upload area:

AcelleMail parses the file and confirms detection:

4. Map the columns#

The wizard auto-detects standard columns (email, first_name, last_name) and shows green Mapped to EMAIL chips. Adjust manually for any non-standard column from the source:

5. Pick duplicate handling#

In the same screen, choose what AcelleMail does when a subscriber already exists in this list:

• Skip — keep the existing row, don't overwrite
• Update — overwrite name/tags/custom fields with values from the CSV
• Unsubscribe — mark existing rows as unsubscribed (rare; used when re-importing an opted-out list)

6. Run the import#

Click Start import. The job runs in the background — close the popup, work elsewhere, return to Audience → [list] → Import to see progress:

You'll see Pending → Running → Complete per import job, with rows-imported / rows-skipped / errors counts.

After the import#

• Verify list count matches your expected size (rows that failed validation appear in the Errors column with a downloadable error CSV).
• Re-tag if needed — for behavioural data that doesn't fit a CSV column (e.g. "opened campaign X"), you may need to re-create the tag via segmentation rules.
• Pause for warm-up — if the imported list is large (>10k) and your sending IP is new or recently rotated, run a short warm-up campaign to your most-engaged 10% before the full send. See IP warm-up best practices for the schedule.

Rebuilding Klaviyo flows in AcelleMail#

Klaviyo's flows map to AcelleMail's Automations. Equivalent triggers:

For Klaviyo's predictive analytics + AI features (predicted CLV, churn risk), AcelleMail doesn't have direct equivalents — these are Klaviyo-specific advantages. If you depend on them, evaluate whether the cost savings of self-hosting justify rebuilding those signals via your own data pipeline.

Merge-tag syntax differences#

Klaviyo's Jinja-style conditionals ({% if profile.tags contains 'vip' %}) work in AcelleMail's email builder with minor adjustments (use subscriber.tags instead of profile.tags).

# Klaviyo Private API key from Settings → API Keys
curl -X GET "https://a.klaviyo.com/api/profiles/?page[size]=100&page[cursor]=" \
  -H "Authorization: Klaviyo-API-Key <KLAVIYO_PRIVATE_KEY>" \
  -H "revision: 2024-10-15" \
  -o klaviyo-profiles.json

ACELLE_TOKEN="..."
ACELLE_LIST_UID="..."

jq -c '.data[] | {email: .attributes.email, first_name: .attributes.first_name, last_name: .attributes.last_name}' klaviyo-profiles.json \
  | while read sub; do
      curl -X POST "https://acellemail.com/api/v1/subscribers" \
        -H "Authorization: Bearer $ACELLE_TOKEN" \
        -d "{\"list_uid\":\"$ACELLE_LIST_UID\",\"subscriber\":$sub}"
    done

Related articles#

• Importing contacts CSV — best practices and field mapping
• Migration from Mailchimp to AcelleMail
• Advanced automation triggers and conditions
• Building a welcome email series in AcelleMail