Migrating from another SMS provider to Klaviyo

You will learn

Learn the steps for migrating from another SMS provider to Klaviyo.

Before you begin

Klaviyo SMS migration steps

Below, we list out what to do when migrating as well as where these steps fall within the Getting Started with SMS course.

• In Orientation:
  
  1. Send a final message from your provider (2 minutes)
  2. Export data from previous SMS provider (11 minutes)
  3. Port phone number (optional) (2 minutes)
• In Add subscribers:
  1. Import SMS contacts (6 minutes)
  2. Create SMS subscribers segment (2 minutes)
• In Build relationships:
  1. Send a campaign from your new number (3 minutes)

Orientation

Send a final message from your previous provider

It's a best practice to tell subscribers when you're about to change your number, and this is required for US short codes and some US wireless carriers.

If you are not changing numbers (i.e., you're porting your number), skip to the section on exporting your data.

A week before changing numbers, send a final message from your previous SMS provider. Some carriers require this, and failure to comply may result in an audit or deliverability issues.

Include the following in the message:

• Your organization’s/brand’s name
• Your new phone number
• Key details about the transition, like support/contact care information (e.g., “Reply HELP for help”)
• Opt-out language (e.g., “Text STOP to unsubscribe”)

Export data from previous SMS provider

Next, export your existing data. The steps for migrating vary depending on your previous SMS provider. In general, though, you will need to:

1. Export SMS contacts
2. Export any additional data you want

If possible, when exporting contacts, we recommend separating subscribers by:

• Country (if you send to more than one country)
• Opt-in status

The first makes it easier when you’re importing consent, while the second ensures that you don’t accidentally send to non-consented subscribers and risk breaching compliance.

Migrating from Yotpo? Check out our Yotpo Email & SMS Migration integration.

Port phone number (optional)

When switching SMS providers, keeping the same number makes for a smoother transition for your subscribers. They’ll recognize the number as being from your brand, so you’ll be able to pick up exactly where you left off.

Note that porting a number results in the loss of any voice capabilities.

You can port toll-free numbers and short codes; however, porting is not available for shared short codes or branded sender IDs.

Allow 2–4 weeks to port a toll-free number or 8–12 weeks to port a short code into Klaviyo.

How to port a phone number
Click your organization name in the bottom left. Navigate to Settings > Text message > Sender information. Select Port existing number. Choose Toll-free number or Short code. For a short code, select its country. Click Continue to open the application in a new tab. Complete and submit the application for your number type. Wait for the Klaviyo SMS team to follow up and help complete the port.

Add subscribers

Import SMS contacts (7 minutes)

1. Format your CSV

Before importing SMS subscribers, set up SMS in Klaviyo with a sending number for each country you plan to import. Only import SMS marketing consent for people who explicitly agreed to receive marketing texts from your brand. Check that your CSV is formatted correctly before uploading it.

In your CSV, you must include:

• Phone number
• Country (either through the country code or as a separate column)

2. Remove opted-out contacts

Before importing your SMS contacts, remove anyone who is no longer subscribed.

Filter your CSV to show only those who are opted out, copy them to a new spreadsheet, and then delete them from the original CSV. Keep the new spreadsheet for the opted-out contact steps below. For consent requirements, see how to upload SMS consent.

3. Upload a CSV of SMS contacts

4. Import opted-out contacts

If you want to add in the information for opted-out contacts, you can upload them into Klaviyo and mark them as unsubscribed. This way, you'll have the data you've already collected but won't risk texting them.

Prepare a separate CSV of opted-out contacts, as described above. Include their phone numbers and country. You will first import their profile information without subscribing them, then use the same file to mark their phone numbers as unsubscribed.

Once that's done, follow these steps:

1. Format and check your CSV.
2. Turn any list-triggered flows (e.g., your welcome series) to manual.
3. Navigate to Audience > Lists & segments.
4. Choose the list to import to (e.g., your main subscriber list).
5. Click the Manage list dropdown.
6. Choose Import contacts.
   

7. Upload your CSV and click Next.
8. Map the profile fields you want to import. Do not map a historical SMS consent timestamp or a consent value that subscribes these contacts.
9. Click Next if shown. If prompted to confirm consent, select Only import the consent in my file. Do not select Apply bulk consent for SMS.
10. Review your mapped fields and consent choices.
11. Click Import.
12. Wait for the profile import to finish and review any skipped records before continuing.
13. Open the dropdown under your account name.
14. Click Settings > Other > Profile maintenance.
15. Scroll to Import text message unsubscribes.
16. Upload your opted-out contacts CSV. Name the phone number column Phone Numbers. Include either international calling codes in the numbers or a Country column.

17. Click Save.
18. Click Unsubscribe Phone Numbers in the confirmation dialog.

The unsubscribe process may take a few minutes. Check its status and review any skipped records before sending to your migrated audience. If you set list-triggered flows to manual, restore them only after the imports are complete and the waiting period above has passed.

Create an SMS subscribers segment

Segments update automatically; profiles will enter or leave the segment when they meet or fail to meet the segment’s conditions. This is different from lists, which are static.

Without a segment, it can also be difficult to know how many SMS subscribers you have, as subscribers may be spread throughout different lists or you may have a list that shows both your email and SMS subscribers together. An SMS segment will show you everyone who is consented to your SMS marketing, letting you see all of your subscribers at once.

How to create an SMS subscribers segment
Go to Audience > Lists & segments > Create > Segment. Name your segment. If a naming dialog appears, click Create segment to open the builder. Add the condition If someone can or cannot receive marketing. Set the condition to Person > can receive > text message marketing. Click Create segment to save the segment.

Build relationships

Send an SMS campaign

What you want to send depends on your audience as well as if you kept the same number when you migrated to Klaviyo.

Journey Check: Click the link that best fits your situation:

• I changed my sending number
• I ported a toll-free number
• I ported a short code
• I previously only used a branded sender ID

If you switched numbers or ported a short code

If you ported a short code or switched SMS sending numbers, your first campaign from your new number should act as a follow-up to your last message from your old number, informing subscribers about the change and how you’ll be texting them going forward.

In the text, you’ll want to let subscribers know certain information, including:

• Your brand’s name
• The recurring-SMS program’s name or product description
• Support/customer care information (e.g., “Reply HELP for help”)
• Opt-out instructions (e.g., “Text END to unsubscribe”)
• Disclosure that message and data rates may apply
• Disclosure for message frequency

Example text: "[Organization Name]: Hi from our new number! Thanks for sticking with us.[Add offer, if desired]. Text STOP to opt out, HELP for help. Msg & data rates may apply. Msgs are recurring."

How to send an SMS campaign (number change)

Navigate to the Campaigns tab. Click Create campaign. Name the campaign. If offered a choice, select Single channel, then select Text message as the channel. Click Continue. Choose which list(s) or segment(s) to send to. Click Next to continue to the message. Write your text in the message editor. Click Next to review the campaign. Review the settings for the campaign, confirming that the message will send to the right audience and tracking is enabled. Click Schedule or send. Choose when to send. For a later send, set the date, time, and timezone, then click Schedule message. To send immediately, select the immediate-send option and click Send now.

If you kept the same number

If you kept the same number (and it’s not a short code) or previously only used a branded sender ID, you’ll want to continue your previous SMS strategy. Were you sending out text alerts every Thursday? If so, keep the same cadence and content. In the first message, though, we recommend including a reminder about who you are and how to opt out.

For future sends, think about how you can use your data in Klaviyo to better target your audience, such as personalizing your messages and creating segments around location, purchase history, gender, etc.

Additional resources