Install and connect Klaviyo

Updated 1 month ago4 min readIntegrations

Overview

Connecting Klaviyo lets Loop read your list of segments and use one of them as the audience of an outbound calling campaign. The connection uses OAuth 2.0, so there is no API key to copy and you can revoke access at any time. Loop only reads from Klaviyo — it never creates or changes anything in your account.

Before you begin

A Loop workspace where you are an admin.
A Klaviyo login that is allowed to authorize integrations.
At least one Klaviyo segment whose members have phone numbers.

Add a “Phone number is set” condition to the segment you plan to call so the estimated reach you see in Loop is realistic.

Option A — Install from the Klaviyo App Marketplace

Click “Install” on the Loop listing
You land on https://app.loopvoice.ai/klaviyo/app-install.
Sign in to Loop if prompted
The sign-in page has a “Create account” link. You are returned to the install page automatically afterwards.
Choose a workspace
If you are an admin of more than one workspace you see “Choose a workspace”. Pick the one that will run the campaigns.
Authorize on Klaviyo
You are redirected to Klaviyo’s consent screen. Click “Allow”.
Done
You land on “Klaviyo connected” — “Loop can now read your Klaviyo segments. Use one as the audience when you build a campaign.” — with a “Go to campaigns” button. If the workspace was already connected you see “Klaviyo is already connected” instead.

If you are not an admin of any workspace you see “Only a workspace admin can connect Klaviyo. Ask an admin on your team to run the install.”

Option B — Connect from inside Loop

Open Team
In the left navigation, click “Team”.
Find the Klaviyo card
Subtitle: “Sync your Klaviyo segments to target campaigns.”
Click “Connect with Klaviyo”
Helper text: “You’ll be sent to Klaviyo to authorize Loop. No API key needed — access is granted securely and can be revoked anytime.”
Click “Allow” on Klaviyo
You return to Team and see a “Klaviyo connected” toast. The card now shows a green “Connected” badge, your Klaviyo account name and a “Disconnect” button.

If the consent screen returns something else: “Authorization was declined. Please authorize access by clicking ‘Allow’ to enable integration.” means you clicked Deny. “That Klaviyo authorization session expired. Start the connection again to continue.” means the consent screen was left open for more than 5 minutes. “Could not connect Klaviyo. Please try again.” covers anything else.

What Loop asks permission for

Scope	What it's used for
`accounts:read`	Used once at connection time to read the Klaviyo account ID and account name so Loop can display “Connected — <Account name>”.
`segments:read`	Used to list your segments (ID, name, type, last-updated) and to read one selected segment’s profile count (shown as “estimated reach”).
`profiles:read`	Used to read the member profiles of the one segment selected for a campaign, requesting only email, phone_number, external_id, first_name, last_name.

Loop never writes to your Klaviyo account.

Verify the connection

Go to Campaigns → New campaign → Audience and choose “Klaviyo Segment”. You should see “Klaviyo connected — <your account>” and your segments in the “Klaviyo segment” dropdown. The segment list is cached for 5 minutes, so a segment you just created may take a few minutes to appear — press “Refresh” to re-read it immediately.

Disconnect or reinstall

In Loop, go to Team → Klaviyo → “Disconnect”. The dialog “Disconnect Klaviyo?” explains: “Loop will be removed from your Klaviyo account and campaigns will no longer be able to target Klaviyo segments. You can reconnect at any time.” On confirm, Loop revokes its OAuth grant with Klaviyo and deletes the stored tokens.

Removing Loop from Klaviyo (Klaviyo → Integrations) works too: the next time Loop uses the connection, Klaviyo reports the grant revoked and Loop removes the connection and shows Klaviyo as not connected. Reconnecting is the same OAuth flow — nothing has to be rebuilt.

Workspaces that connected before 21 August 2026 were granted only accounts:read and segments:read. Those connections show an amber “Reconnect to target segments” warning; click “Reconnect Klaviyo” and authorize again. Nothing is lost.