The Ultimate SMS Migration Guide for 2025 - Klaviyo
2026-03-10 16:36 Diff
https://www.klaviyo.com/marketing-resources/sms-migration-guide

The ultimate SMS migration guide

A step-by-step blueprint for moving your SMS marketing program to a new platform

Introduction

As your business scales, your SMS marketing strategy and tools have to evolve as well. What might have been the best SMS marketing platform for your business a year ago may no longer be the best fit today.

As your customer base grows, you need a platform that can scale your operations efficiently without getting bogged down in complex technical set-ups.

While migrating to a new SMS provider can seem challenging, it doesn’t have to be overwhelming. With the right approach, you can smoothly manage the process of transferring data and adjusting workflows, ensuring your marketing continues running seamlessly without notable disruptions.

Below, we’ll walk through some best practices to consider when migrating to a new SMS marketing platform, such as how to export data, import subscriber lists, and more.

How to prepare for an SMS migration

Migrating to a new SMS provider involves several critical steps to ensure a smooth transition—for both your team and your customers. Regardless of which platform you’re moving from, consider the following:

  1. Record the performance of your forms, segments, campaigns, and individual flow messages. See which messages perform best, who your most engaged subscribers are, and which forms lead to the most conversions. This can give you a good idea of what to replicate, test, or improve when you migrate.
  2. Understand your current flows and set-up by taking the time to map out your current automated flows (such as welcome sequences, abandoned cart reminders, post-purchase follow-ups, and any other triggered messages). By documenting these flows in detail, including their timing, content, and targeting rules, you can replicate and update them on the new platform without losing continuity.
  3. Review the attribution windows between your current and new platform. Different platforms track sales and clicks for different lengths of time. For example, some platforms might credit an SMS message for a sale that happens up to 30 days after someone clicks your link. Others might only give credit for sales made in 5 days or even just 24 hours. You will want to understand these differences, as they can significantly impact your reported revenue and performance metrics.
  4. Communicate any expected changes in advance to the rest of your team and your manager. Outline the migration timeline, potential service interruptions, and the new platform’s features. This ensures that everyone is aligned and prepared for any operational changes, such as updates to reporting metrics, new workflows, or different user interfaces.
  5. If you’re switching to a new phone number (toll-free or short code), send a final message to your subscribers from your current number. Some carriers require this, and skipping it could trigger an audit or hurt your message delivery rates. About one week before the switch, send a message that includes:
  • Your brand nameYour new phone numberKey details about the transition (like support information)Opt-out language (e.g., “Text STOP to unsubscribe”)
    • Your brand name
    • Your new phone number
    • Key details about the transition (like support information)
    • Opt-out language (e.g., “Text STOP to unsubscribe”)

How to export data from your existing SMS provider

Most SMS providers don’t let you export your own data directly from their platform. You’ll need to formally request it from them. This process requires careful planning and clear communication because once you lose access to your old platform, you can’t retrieve missed information.

Here’s what to prioritize:

These consent records, especially opt-in timestamps, are legally required under regulations like TCPA and GDPR. Each subscriber record should include:

  • Phone number
  • Opt-in timestamp
  • Opt-in source (like a specific form or check-out page)
  • Any opt-out dates and reasons

Never import subscribers without clear consent documentation. If you’re missing any consent records, consult your legal team before proceeding. While some platforms might suggest using engagement data (like recent clicks) to identify active subscribers, this usually isn’t a reliable substitute for proper consent records.

How to import your existing SMS subscribers

When importing subscribers from your previous platform, you have two options: create a new list, or add to an existing one. We recommend creating a new list and using double opt-in for SMS, which is a crucial compliance safeguard.

  1. Check your data format requirements:
    Every number must include the country code or otherwise indicate the recipient’s country of residence.Remove any special characters or spaces from phone numbers.Verify all dates use the same format.
    • Every number must include the country code or otherwise indicate the recipient’s country of residence.
    • Remove any special characters or spaces from phone numbers.
    • Verify all dates use the same format.
  2. Ensure opt-outs are saved to a separate CSV from your list import. You can choose one of the following methods to manage your opt-outs:
    Recommended: Upload these contacts separately through your settings page.Alternative: Keep an internal record of these opted-out profiles.
    • Recommended: Upload these contacts separately through your settings page.
    • Alternative: Keep an internal record of these opted-out profiles.
  3. Make sure you have a dedicated list to import to. When you set up a new list for your SMS subscribers, use double opt-in for future subscribers.

Pro tip: Some providers put both opt-outs and opt-ins in the same CSV. If this is the case for your CSV, it’s important to remove all unsubscribed SMS profiles from your CSV. It’s generally advisable  to retain any opt-out information for future reference.

3 ways real brands fine-tuned their strategy after switching to Klaviyo SMS

If you’ve chosen a solid SMS marketing platform to migrate to, it should set you up for success. Here are a few examples of what SMS migration can help brands like yours do (or do more easily):

Leonisa, a brand that specializes in lingerie, shapewear, swimsuits, and activewear, migrated to Klaviyo from their previous SMS marketing platform, Attentive.

One key strategy the team has adopted is to show device-targeted SMS sign-up prompts to mobile shoppers, which increases the chances of conversion. Leonisa’s pop-ups in the US see as much as 1.6x the median form fill rate for their peer group, according to Klaviyo benchmarks.

Pro tip: For best results with your own forms, match them to how people browse. On desktop, use traditional forms where visitors type in their phone numbers. For mobile visitors, implement Smart Opt-in for click-to-text functionality—this makes subscribing effortless.

Frequently asked questions about migrating SMS platforms

The timeline depends on 3 main factors:

  1. How much data you need to move
  2. How complex your current set-up is
  3. How quickly you can get your data from your current provider

While the actual migration might take just a few days, exporting your data can take longer. Some providers require you to submit formal requests for your data or may have waiting periods.

As for short codes, the registration (or re-registration) process can stretch to several weeks.

Pro tip: Start requesting your data early in the planning process. Even if you’re just exploring a switch, having your data ready will save you time later.

Glide through your SMS migration with Klaviyo

A carefully planned SMS migration to a well-chosen platform can have a significant impact on your business. But a successful migration is just the beginning.

The true potential of SMS marketing lies in how you leverage the data it provides and refine your strategies over time. Focus on expanding your SMS offerings, testing different approaches, and integrating follow-up email campaigns to enhance customer engagement.

With Klaviyo’s intuitive segmentation tools, you can unlock new opportunities for growth, such as built-in consent and compliance features and robust automation capabilities that’ll get you up and running quickly post-migration with minimal disruption.

Get a hands-on look at how easy it is to migrate to Klaviyo.