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Integration Guide

How to Sync GrowSurf Referral Data to MailerLite Subscribers

One API key, one Group, 15 referral fields — on MailerLite Classic, which is the part to check first.

Want the full setup walkthrough?

Use these docs for exact setup steps, supported fields, and troubleshooting.

GrowSurf MailerLite setup guide MailerLite custom fields help

GrowSurf adds and updates subscribers in the MailerLite Group you choose and creates the fields holding each participant’s referral link, referral counts, referrer details, and milestone progress.

This integration works with MailerLite Classic. If your account is on MailerLite New, the direct integration does not apply — you can still connect the two through Zapier or Webhooks. Check which one you are on before you start.

Integration Steps

Confirm you are on MailerLite Classic

GrowSurf’s MailerLite integration supports MailerLite Classic. On MailerLite New, use Zapier or Webhooks instead. The integration card in GrowSurf states this too, so you will not get far down the wrong path.

Get your MailerLite API key

Copy your API key from MailerLite > Integrations > API.

Connect MailerLite in GrowSurf

Open Program Editor > 4. Options > Integrations and search for MailerLite.

Searching for MailerLite in the GrowSurf Program Editor integrations list
Search the integrations list in Program Editor > 4. Options > Integrations.

Expand the card, paste the API key, and submit.

The MailerLite API key field in GrowSurf, with a note that only MailerLite Classic is supported
The card states the MailerLite Classic requirement before you paste a key.

Connect before importing participants; the sync covers people added from that point on. Already imported? Use the existing-participant sync options.

Choose the Group and save

MailerLite organizes by Group. Pick the one that should receive GrowSurf participants and save changes.

Know your fields

GrowSurf dataVariableTypeWhat it holds
Share URL{$grsf_share_url}TextThe participant’s unique referral link
Participant ID{$grsf_participant_id}TextThe participant’s GrowSurf ID
Referral Status{$grsf_participant_referral_status}TextCREDIT_PENDING, CREDIT_AWARDED, or CREDIT_EXPIRED
Participant first name{$grsf_participant_first_name}TextThe participant’s first name
Participant last name{$grsf_participant_last_name}TextThe participant’s last name
Referrer first name{$grsf_referrer_first_name}TextThe referrer’s first name, when there is one
Referrer last name{$grsf_referrer_last_name}TextThe referrer’s last name, when there is one
Referrer email{$grsf_referrer_email}TextThe referrer’s email, when there is one
Total referral count{$grsf_total_referral_count}NumberAll-time referral count
Monthly referral count{$grsf_monthly_referral_count}NumberReferral count for the current month
Previous monthly referral count{$grsf_prev_monthly_referral_count}NumberReferral count for the previous month
Next milestone{$grsf_next_milestone}TextThe next milestone message, on programs with milestone rewards
Next monthly milestone{$grsf_next_monthly_milestone}TextThe next monthly milestone message, when there is one
Total invite count{$grsf_total_invite_count}NumberAll-time invite count
Total impression count{$grsf_total_impression_count}NumberAll-time referral-link view count

MailerLite variables use {$name}. Use them exactly as shown in campaign content.

Tips

Classic or nothing

This is the first thing to verify. A MailerLite New account cannot use the direct integration no matter how the key is configured.

Group, not list

MailerLite calls it a Group. GrowSurf writes subscribers into the one you select.

The dollar sign is part of the syntax

{$grsf_share_url} resolves; the same name without $ does not.

Recommended Guides

How to Add Referral Links to MailerLite Campaigns

MailerLite variables put each subscriber’s own referral link into a single campaign or automation.

View Guide →

How to Sync GrowSurf Referral Data to EmailOctopus

One API key, one list, and every contact carries their referral link as a custom field.

View Guide →

How to Sync GrowSurf Referral Data to AWeber Subscribers

Connect AWeber, pick a list, and every subscriber carries their own referral link and progress as custom fields.

View Guide →

FAQ

Does this work with MailerLite New?

No. The direct integration supports MailerLite Classic. For MailerLite New, connect through Zapier or Webhooks.

Where do I get the API key?

MailerLite > Integrations > API.

What is the variable for the referral link?

{$grsf_share_url}.

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