This page answers common questions about the Klaviyo integration — the permissions and plan you need, which types of sends can trigger LINE, and what to do when something doesn't work.
What permissions and plan do I need for the Klaviyo integration?
The Klaviyo integration requires an account with permission to approve app integrations in Klaviyo.
You approve the integration during Klaviyo setup, at the step where you authorize the app integration on the Klaviyo side. Use an account that has permission to change account-wide settings and authorize app integrations, such as an administrator account. Eligibility based on your Klaviyo plan follows whatever Klaviyo currently offers. Because day-to-day operation includes email and SMS delivery, we recommend a plan that lets you use delivery features.
Permission guidelines
| Item | Details |
|---|---|
| Klaviyo permission | Permission to approve app integrations (such as administrator permission) |
| When approval happens | Approve the app integration during Klaviyo setup |
| Eligibility | Depends on your Klaviyo plan. A plan with delivery features is recommended for real operation |
Can I send LINE messages from a Klaviyo Campaign?
No. Klaviyo Campaigns (mass sends) have no Webhook action, so you cannot send LINE directly from a Campaign.
Campaign-style mass LINE broadcasts go out from Lumo's Message Broadcast. If you specify a Segment built from Klaviyo conditions (lists, properties, ID linkage) as the recipients, you can reach the target audience you manage in Klaviyo on LINE as-is. Scenario-driven automated sends are done from a Webhook action in a Klaviyo Flow. With either route, delivery results are recorded on Klaviyo profiles.
How do I send a LINE message from a Klaviyo Flow?
Add a Webhook action to your Klaviyo Flow and enter Lumo's setup values to send.
The setup flow is as follows.
Setup steps
- In Lumo, create an auto send message and check the Destination URL, header (Key / Value), and JSON body under "Klaviyo Flow connection details" on its detail page.
- Add a Webhook action to your Klaviyo Flow and set the Destination URL and header you confirmed.
- Copy the JSON body with "Copy JSON" and paste it into the request body of the Webhook action. The merge variable for the recipient is included automatically.
How to specify the message to send
| Method | Details |
|---|---|
| Use an Auto Send Message | Paste and send the JSON body generated under "Klaviyo Flow connection details" on the auto send message's detail page |
| Enter text directly | Specify the text you want to send with messageText instead of autoMessageId in the JSON body |
Sends from a Flow are slow or not arriving — why?
Due to processing on the Klaviyo side, it can take anywhere from tens of minutes to about an hour from when the event occurs to when the Webhook runs.
This is due to how Klaviyo ingests events and processes Flows; Lumo sends to LINE promptly as soon as it receives the request from Klaviyo. To verify that your setup is correct, use Klaviyo's Payload Preview and a test send rather than waiting for an actual delivery.
If messages are not arriving at all, check the following in order.
- Whether the recipient customer has completed ID linkage between LINE and Klaviyo (if not linked, the recipient cannot be identified and the message does not arrive)
- Whether the Flow and the Webhook action are Live (published) — they can revert to Draft after saving
- Whether the Webhook's header (Key / Value) matches the value in "Klaviyo Flow connection details"
Also, if more than 6 hours pass between when the event occurs and when it is ingested into Klaviyo, the Flow will not be triggered for that event (this is Klaviyo's specification).
Can I send LINE to friends who are not ID-linked?
It depends on the route. Lumo's Message Broadcast can send to them; sends via a Klaviyo Flow cannot.
- Lumo's Message Broadcast: You can broadcast to all of your LINE friends (it reaches friends who are not ID-linked, too). However, if you set a Segment built from Klaviyo conditions as the recipients, only ID-linked friends are included
- Sends via a Klaviyo Flow: These reach only ID-linked customers. If a customer is not linked, the recipient cannot be identified, so they are skipped
- LINE notification messages: These reach customers who are not friends, as long as the phone number on the Klaviyo profile matches the number registered to their LINE account (strictly for transactional notifications such as order and shipping confirmations)
Note that event recording in Klaviyo (opens, clicks, and so on) happens only for ID-linked customers, regardless of the route.
Do I need a profile filter so only ID-linked customers go through the Flow?
No, you do not. Lumo automatically skips sends to customers who are not ID-linked, so the Flow runs safely without a filter.
The Webhook action runs for every customer who reaches that step in the Flow, but when Lumo receives the request, it identifies the recipient and does not send to customers who are not ID-linked (no error occurs, either). Messages are never delivered to non-linked customers by mistake.
Note, however, that the Sent count shown on Klaviyo's Webhook action is the number of times the webhook ran, not the number of LINE messages actually sent. If you want a number closer to the actual recipients, add a Conditional Split just before the Webhook action (for example, the property "LINE User ID" is set). Narrowing the entire Flow with a profile filter also limits email sends in the same Flow, so use a Conditional Split when you only want to narrow the LINE step.
Can I send LINE notifications to customers before they add me as a friend?
Yes. Transactional notifications such as order and shipping confirmations can reach customers before they add you, using LINE notification messages.
A LINE notification message is a notification-only message certified by LY Corporation that reaches a customer even if they are not your friend, as long as their phone number matches the number registered to their LINE account. Triggered by a Webhook action in a Klaviyo Flow, it can carry merged values such as the order number and tracking number. Using it requires an application to and approval from LY Corporation, and it cannot be used for advertising or promotions. The setup is explained in Send LINE Notification Messages from a Klaviyo Flow.
Could the same message or notification arrive twice?
Even if Klaviyo resends a Webhook or a Flow fires twice, duplicate sends are prevented automatically.
The JSON body generated under "Klaviyo Flow connection details" includes a deduplication key (idempotencyKey), so even when the same order or checkout event arrives repeatedly, only one message is sent to the same customer. Flows where repeated delivery is legitimate — browse reminders, low-stock alerts, and restock notices — do not carry the key. If you are using a JSON body you obtained earlier, get the latest JSON and paste it again to enable this.
Can I carry over ID links made with another tool?
Yes. With ID link import, you can bring in ID links already made with another tool in bulk.
From "ID link import" on the "Settings" tab of the Klaviyo or Shopify integration, upload a CSV file with two columns — email address and LINE User ID. Imported links propagate to all connected integrations. Only customers who are already LINE friends are linked. Link data that another LINE integration tool stored on Shopify customers can also be imported automatically from the Shopify integration settings.
How do I link a Klaviyo profile to a LINE friend?
You can link IDs in several ways, using the email address, phone number, or LINE User ID as the key.
Choose from the following methods to match your customer flow.
| Linking method | Overview |
|---|---|
| Custom QR Code | Insert a custom QR Code into a Klaviyo email and link when the customer adds you as a friend |
| Link IDs from form submissions | After a Klaviyo form is submitted, show a linking button or QR Code to link |
| Link IDs from Flows | Automatically match by email address from a Webhook action on an existing Klaviyo Flow |
| Link IDs from segments | Read existing LINE User IDs from profiles in a Klaviyo Segment and link them |
| Automatic linking from synced data | Link automatically during data sync, using the email address or phone number as the key |
| ID link import | Import ID links made with other tools in bulk from a CSV file (email address + LINE User ID) |
Can I send a custom QR Code from a Klaviyo email to link accounts?
Yes, you can.
When you set Klaviyo as the linking type on a Lumo custom QR Code and specify a Klaviyo merge variable (the email address), a per-customer linking URL is generated. Insert this URL into a Klaviyo email and send it, and when a customer adds you as a friend, the corresponding Klaviyo profile and LINE user are linked automatically.
Where do product cards get their product data?
Content feeds such as best sellers, newest, and on sale use product data synced directly from your Shopify store.
To use them, install the Lumo app on both Klaviyo and Shopify. Product cards that use "Trigger products," such as the abandoned cart follow-up, use the product information contained in the event that triggered the Flow, so they work without product data sync with Shopify.
No products appear on the product card's "Best sellers" feed
A best-sellers content feed selects products based on sales records, so products with no sales are not shown.
In stores that still have little sales data — such as right after opening — there may be no products to show, and the message may display as text only. In that case, the fallback products are shown instead. Right after launch, we recommend using a "Newest" feed or fallback products, then switching to "Best sellers" once sales data has accumulated.
Can I use LINE opens and clicks in Klaviyo?
Yes, LINE behavior is recorded as Klaviyo events and can be used.
LINE message sends, opens, and clicks, as well as friend additions and blocks, are recorded as events on ID-linked Klaviyo profiles. You can use these events to build Klaviyo segments, analyze them in reports, and trigger Flows.
Is a LINE open the same as "Read" in the LINE app?
No, they are different metrics.
Opens (Opened LINE Message) come from Lumo's measurement mechanism and are different from "Read" in the LINE app. Opens and clicks are recorded for messages that include a trackable link or image.
Can I tie revenue to LINE sends?
Klaviyo's revenue attribution (attributed conversion) does not automatically apply to LINE sends from Lumo.
That is because Klaviyo's revenue attribution is a mechanism designed for email and SMS sent from Klaviyo. When you want to see the revenue impact of your LINE campaigns, combine methods such as adding UTM parameters to the links you send and measuring with web analytics, or analyzing purchases by the Segment that reacted on LINE.
Can I run LINE broadcasts using Klaviyo segments?
Yes, you can use Klaviyo data to target LINE broadcasts.
You can specify Klaviyo integration data (link status, lists, properties) as conditions for a Lumo Segment. Using this Segment, you can narrow down the audience for a Message Broadcast or show different Rich Menus to different people. You can reach the same target audience on LINE as your email campaigns.
Note that a segment here means the conditions used to narrow down a delivery audience. It is a different concept from the tags you attach to friends. If you want to attach Klaviyo data to friends as tags, manage it with the tag feature.
Can I connect multiple LINE Official Accounts to one Klaviyo account?
Yes, you can.
When you connect multiple LINE Official Accounts, a number is appended to the end of the property names written to Klaviyo profiles (for example, LINE User ID 2) to distinguish the accounts. Settings and syncing are managed separately for each account.
Which Klaviyo data is synced?
Lumo writes LINE information into Klaviyo as custom properties.
The LINE User ID, LINE display name, LINE follow status, LINE consent status, and more are synced to Klaviyo profiles. Profile fields such as first name, last name, email address, and phone number, on the other hand, are not synced from Klaviyo to Lumo by default. You can add the fields you want to bring into Lumo on the "Sync Data" screen.
Sync direction overview
| Direction | Main data |
|---|---|
| Lumo → Klaviyo | LINE User ID, LINE display name, LINE follow status, LINE consent status, and more |
| Klaviyo → Lumo | First name, last name, email address, phone number, and more (not synced by default, so add them under "Sync Data") |
What happens when I reissue the authentication key for Flow message sending?
When you reissue it, the old authentication key stops working immediately.
Update the header Value set on the Klaviyo Flow side to the new authentication key as well. If you do not, LINE delivery and ID linking from the Flow will fail with an authentication error and stop working. You can regenerate the key from "Regenerate auth key" in the "Link IDs from Flows" section on the "Settings" tab of the Klaviyo integration.
How is the LINE consent status in Klaviyo updated?
It is updated automatically based on the LINE friend status.
When a customer adds you as a friend, this is reflected as consent given, and when they block you, as consent withdrawn, automatically updating the LINE consent status on the linked Klaviyo profile. On the Klaviyo side, you can use this consent status as a condition for segments and Flows. Changes in friend status are reflected in Klaviyo periodically, so no manual update is needed.
This updates the consent status on the Klaviyo side to the latest value; it does not change the actual LINE follow status itself.
What should I do if the integration was disconnected or I am asked to reconnect?
When Klaviyo authorization becomes invalid, a reconnection notice appears on screen. Reconnect from the notice and syncing resumes automatically.
When Klaviyo authorization becomes invalid, syncing stops and a notice reading "Authorization for Klaviyo is no longer valid, so syncing is paused. Please reconnect." is displayed. When you reconnect from "Open reconnect settings", syncing resumes. If reconnecting does not resolve it, please contact support.
If LINE delivery or ID linking from Klaviyo Flows fails with an authentication error, the cause may instead be a reissued Flow message sending authentication key. In that case, also check "What happens when I reissue the authentication key for Flow message sending?".
If I remove the integration, is the data on the Klaviyo side deleted?
No, the data written to Klaviyo remains on the Klaviyo side.
Data written to Klaviyo, such as the LINE User ID and custom properties, is not deleted. What is stopped or deleted when you remove the integration is the periodic sync with Klaviyo and the sync history brought in from Klaviyo. If you re-sync from Lumo after re-integrating, the link by LINE User ID is recreated.
What remains and what is removed when you disconnect
| Category | Details |
|---|---|
| Remains on the Klaviyo side | Already-written data such as the LINE User ID and custom properties |
| Stopped or deleted | The periodic sync with Klaviyo and the sync history brought in from Klaviyo |