How to Switch SMS Providers Without Losing Contacts (Migration Guide)

Switching SMS providers sounds more complicated than it is. Most businesses put it off because they worry about losing contacts, disrupting active campaigns, or having to start over with a new phone number. In practice, a well-planned migration takes one to three working days and results in zero lost contacts and no service interruption.

This guide walks through the full process: what to export from your current provider, how to clean and import your contact list, how to port your existing phone numbers, and how to handle the specific steps for migrating from Twilio or another API-based provider.

When Should You Switch SMS Providers?

Not every frustration with a platform warrants a migration. But if you are experiencing any of the following, it is worth making the move:

• You are paying too much per message and have found a provider with better pricing at your volume
• The platform lacks features you need, such as AI auto-reply, two-way messaging, or agency workspaces
• You are on Twilio and every change requires developer time
• Compliance tools are missing and you are managing opt-outs and consent tracking manually
• Support is slow or unhelpful when things go wrong
• Pricing is unpredictable with variable per-message billing and hidden fees

If two or more of these apply, the cost and effort of switching is almost certainly lower than the ongoing cost of staying.

Compare current platforms at our SMS provider comparison page.

Phase 1: Export Your Contacts

The first step is getting your contact data out of your current platform. The specifics depend on which provider you are leaving, but the principle is the same for most.

What to export

At minimum, export:

• Phone numbers (in international format: +614XXXXXXXX)
• First names and last names
• Any tags or segments you use for targeting
• Opt-out lists (numbers who have replied STOP)
• Consent records if you have them documented

Exporting your opt-out list is critical. If you import only your active subscriber list without your suppression list, you risk sending messages to people who previously opted out. Under the Spam Act 2003, sending to opted-out contacts is a compliance violation.

Export steps for common providers

From MessageMedia

1. Log into your MessageMedia account
2. Go to Contacts and select all contact groups
3. Click Export and download as CSV
4. Go to Opt-outs / Unsubscribes and export that list separately

From Burst SMS

1. Go to Contacts in your Burst SMS dashboard
2. Select your lists and use the Export function
3. Also export your blacklist (opted-out numbers) from Account Settings

From ClickSend

1. Go to Contacts and select the lists you want to export
2. Use the Export to CSV option
3. Export your unsubscribe list from the SMS Unsubscribers section under Settings

From Twilio (via API or database)

Twilio does not have a built-in contact management system, so your contacts likely live in your application database or CRM. Export from there instead. If you have a opt-out list managed in your application, export that as well.

Phase 2: Clean and Format Your Contact List

Raw exports from SMS platforms often have formatting inconsistencies. Before importing into Monster SMS (or any new provider), clean your CSV file:

1. Standardise phone number format: All numbers should be in international format without spaces or special characters. Australian mobiles should be +61XXXXXXXXX (drop the leading 0, add +61). Example: 0412345678 becomes +61412345678.
2. Remove duplicates: Sort by phone number column and remove duplicate rows.
3. Remove invalid numbers: Remove entries that are clearly invalid (less than 10 digits, non-mobile numbers if you only send to mobiles).
4. Consistent column headers: Monster SMS expects columns named phone, first_name, last_name, and any custom fields you define. Rename your columns to match.
5. Check your opt-out list: Cross-reference your active list against your opt-out list and remove any numbers that appear in both.

A simple spreadsheet tool like Google Sheets or Excel handles all of this. Most cleanups take 30 to 60 minutes for lists under 10,000 contacts.

Phase 3: Import Into Monster SMS

1. Sign up for a Monster SMS account at app.monstersms.ai/sign-up
2. Go to Contacts in your dashboard and select Import
3. Upload your cleaned CSV file
4. Map the columns in your CSV to the Monster SMS contact fields
5. Select which list or group to import into (create new groups that mirror your previous segmentation)
6. Confirm the import and wait for it to process (typically a few minutes for lists under 50,000)
7. Review the import summary for any numbers that failed to import and investigate if necessary

Importing your opt-out list

After your contacts are imported, import your opt-out list separately. In Monster SMS, go to Settings > Suppression List and upload your opt-out CSV. These numbers will be automatically excluded from all future sends.

Phase 4: Port Your Phone Numbers

Porting your existing phone number to Monster SMS means you keep the number your customers know and have saved in their phones. The porting process in Australia typically takes 5 to 10 business days.

Which numbers can be ported?

• Australian long codes (04XX numbers assigned to your account by a previous provider)
• Twilio Australian numbers (Monster SMS has a specific Twilio number import process)
• Numbers from MessageMedia, Burst SMS, ClickSend, SMSGlobal, and most other AU providers

Shared sender IDs (like an alphanumeric name you used on another platform) are not numbers and cannot be ported. You register a new sender ID with Monster SMS directly.

How to initiate a number port

1. Contact Monster SMS support at [email protected] with the numbers you want to port and the name of your current provider
2. Monster SMS will initiate the porting request and send you a Letter of Authorisation (LOA) to sign
3. Return the signed LOA. For some providers, you may also need to provide your account number or a recent invoice as proof of ownership.
4. Monster SMS lodges the porting request with the carrier
5. Porting completes within 5 to 10 business days

Running parallel during porting

During the porting window, you can continue sending from your old provider using the original number while Monster SMS is being set up with a temporary number. Once the port completes, switch your sending number in Monster SMS to the ported number and decommission the old account.

Phase 5: Migrate from Twilio Specifically

Migrating from Twilio has a few extra steps compared to migrating from a consumer SMS platform, because your infrastructure (templates, sending logic, contact management) likely lives in code rather than a dashboard.

Inventory what you have built on Twilio

Before migrating, document every SMS workflow that currently runs through Twilio:

• Outbound campaign sends (what triggers them, what templates they use)
• Inbound reply handling (keyword auto-replies, webhooks that receive and process replies)
• Scheduled sends (reminders, follow-up sequences)
• Opt-out processing (how you currently handle STOP replies)

Replace code logic with Monster SMS features

Most Twilio workflows can be replicated in Monster SMS without any code:

• Campaign sends: use the Monster SMS campaign builder
• Scheduled reminders: use the automation and scheduling features
• Inbound reply handling: set up an AI agent or keyword rules in Monster SMS
• Opt-out processing: Monster SMS handles this automatically

For workflows that need to remain code-triggered (e.g., your application sends an SMS on a specific event), replace Twilio API calls with Monster SMS API calls. The Monster SMS REST API uses standard HTTP requests with API key authentication, documented at the features page.

API call changes

A typical Twilio API call looks like this:

The Monster SMS equivalent:

The structure is similar and the change is straightforward for any developer familiar with REST APIs.

Phase 6: Test Before Going Live

Before decommissioning your old provider, run a parallel test period:

1. Send a test campaign from Monster SMS to a small group (your own numbers, team members)
2. Confirm delivery, sender ID display, and message content
3. Test inbound replies and confirm they are handled correctly by your AI agent or routing rules
4. Test opt-out handling: reply STOP from a test number and confirm the contact is suppressed
5. If you have API integrations, test each endpoint and confirm messages are being sent and received
6. Check delivery receipts and reports in the Monster SMS dashboard

Run the parallel period for at least a week before closing your old account, especially if you have time-sensitive campaigns or compliance obligations.

Migration Checklist

How Long Does a Migration Take?

For most businesses:

• Contact export and import: 1 to 3 hours
• Template rebuild: 1 to 4 hours depending on how many templates you have
• API integration updates: Half a day to a full day for complex setups
• Number porting: 5 to 10 business days (can run in parallel with the rest of the migration)
• Testing: 1 to 3 business days

The number porting timeline is the longest step, but it runs in the background while you are setting up everything else. For most businesses, the hands-on migration work is 4 to 8 hours spread across two or three days.

The Monster SMS support team at [email protected] is available to assist at any stage of the migration. For large contact databases (100,000+) or complex API integrations, we recommend contacting support before starting to plan the migration together.