Messaging Setup.

SMS setup and troubleshooting guide, for switching from Android or iOS to a de-Googled, minimal, or feature phone.

This guide is a setup checklist to work through before switching from an iPhone or Android smartphone to a de-Googled phone, minimal phone, feature phone, or custom ROM device.

Complete ALL setup steps in Part 1, in order, BEFORE removing your SIM or eSIM. Doing this out of order is what breaks your texts.

Following the order dramatically reduces broken texts, missing group messages, and delivery failures. You will likely experience disruptions with some group messages. Group messages tend to be the trickiest part and will give you the most problems in the short term, but the SLEKE. team and community is here to help you through it.

If you have already switched phones and are experiencing problems, the same steps still apply, but may take longer or require carrier help. If that is you, skip to Part 2.

How to use this guide

This is a procedure to move your phone number between messaging systems.

• If you have not moved your SIM yet: start at Part 1 and proceed in order.
• If you already moved your SIM: start at Part 2, but expect delays and possible carrier intervention.

Helpful background (so you can sound smart at dinner parties)

Modern phones use three incompatible messaging systems.

• SMS/MMS is old, universal, and works on all phones.
• iMessage is Apple only, sticky, and its group chats persist indefinitely.
• RCS is Google and the carriers, now default on both Android and iPhone.

When you move your SIM without deregistering first, other phones keep trying to reach you using iMessage or RCS, which your new phone cannot receive. Messages get stuck on the wrong track. This guide forces them onto the SMS/MMS track.

The solution: deregister from RCS and iMessage before switching phones. Like cancelling a subscription, you need to opt out while you still have access.

Part 1: Setup guide

Do all of this before switching your SIM or eSIM between devices. Follow the steps in order while your SIM is still in your smartphone. Do not skip steps, even if they seem unnecessary.

For eSIM users: save your carrier's eSIM activation QR code or instructions before deactivating your smartphone. Some carriers allow the same eSIM profile on multiple devices temporarily. If yours does, activate the eSIM on your new phone before deactivating it on your smartphone, so you can test messaging before fully committing to the switch.

Step 1 (iPhone): Disable iMessage, FaceTime and RCS

Do this at least 3 days before switching phones. Apple's systems can take up to 3 days to fully deregister your number.

Disable iMessage

1. With your SIM or eSIM still in your iPhone, open Settings.
2. Go to Settings > Apps > Messages and toggle iMessage off.
3. Tap Send & Receive and verify your phone number is deselected.
4. Visit selfsolve.apple.com/deregister-imessage.
5. Enter your phone number and complete the verification process.

Disable FaceTime

Multiple users report messages did not work until FaceTime was also disabled. Do not skip this step.

1. Go to Settings > Apps > FaceTime.
2. Toggle FaceTime off.

Disable RCS on iPhone (iOS 18 and later)

Newer iPhones use RCS by default. You cannot turn RCS off without the SIM card in the iPhone, so this must be done before removing your SIM.

1. Go to Settings > Apps > Messages > RCS Messaging.
2. Toggle RCS Messaging off.
3. Confirm iMessage is off.

The iOS 18 silent drop. Starting with iOS 18, when an iPhone group chat upgrades to RCS, non-RCS participants are silently removed. No notification is sent to anyone, and the sender sees no error. If you are on a de-Googled phone or custom ROM that cannot register for RCS, you will simply stop receiving those group messages with no explanation. This is why creating new SMS/MMS group chats, rather than continuing old ones, matters so much.

Wait at least 72 hours before removing your SIM or eSIM

Waiting three days gives the messaging systems time to propagate your deregistration across all servers, and ensures Apple's servers fully deregister your number. During this period your message bubbles should turn green, and you should still receive messages as normal on your iPhone. This prevents the iMessage limbo where messages fail to deliver as SMS/MMS.

If you put your SIM back in your iPhone for any reason after disabling iMessage, check immediately that iMessage has not re-enabled itself. iPhones have been observed silently re-enabling iMessage when a SIM is reinserted, which restarts the deregistration clock.

iPad and Mac users: deregistering your number does not stop messages reaching your iPad or Mac if any of these are true:

• Contacts are messaging your Apple ID email address instead of your phone number.
• You have SMS forwarding enabled from your iPhone.
• Your number was not fully deregistered.

Step 1 (Android): Disable RCS

Do this as early as possible before switching phones. Android systems can take up to 30 days to fully deregister your number.

On-device deactivation gives you a 30-day grace period. Online deregistration removes you from all RCS group chats immediately. The 30-day deactivation period resets each time you deregister RCS online, so do not do this repeatedly.

Option A: On-device (preferred)

1. With your SIM still in your Android phone, open Google Messages.
2. Tap Menu, then Settings > Chat features / RCS Chats.
3. Toggle RCS off and confirm when prompted.
4. You will be removed from RCS group chats after 30 days.

Option B: Online deregistration

Your only option if you no longer have your original device.

1. Visit messages.google.com/disable-chat.
2. Follow the instructions for deregistering without the device.
3. Complete verification.

Step 2: Prepare for the SIM swap

If using a physical SIM card

1. Power down both phones completely. This ensures clean network handoffs and prevents conflicts.
2. Remove the SIM card from your smartphone.
3. Insert it into your new phone.
4. Power on your new phone.

If using an eSIM

You do not need to power down both devices. Wait for complete deactivation on the first device before activating on the second. Each carrier's process varies and can change over time, so if these do not match your carrier's current interface, contact support.

AT&T: visit the myAT&T website or app, go to My devices or Device settings, select the device with the active eSIM, choose Update device or Replace device, then follow the prompts.

Verizon: open the My Verizon app or verizon.com, go to Devices, select Activate or switch device, choose the line with the eSIM, then select the new device.

T-Mobile: open the T-Mobile app or t-mobile.com, go to My Account > Phone, select Change SIM, choose Use eSIM, then scan the QR code on the new device.

Then deactivate the eSIM on your smartphone, wait a few minutes, and activate it on your new phone.

Step 3: Configure your new phone for individual and group SMS/MMS

Enable mobile data

MMS, including group texts, requires mobile data to work, even if you do not use data for anything else.

1. Open Settings.
2. Find Network or Connections settings.
3. Toggle Mobile Data on.

Configure group messaging settings

This is the most important setting for group texts.

1. Open your messaging app.
2. Go to Settings > Advanced > MMS / Group Messaging.
3. Enable Send a single MMS to all recipients, not Send individual SMS messages.
4. Verify group messaging is enabled.
5. Verify MMS is enabled.

Step 4: Re-train your messaging

Messages may fail occasionally for the first few days while other phones re-learn that your number only supports SMS/MMS. This is normal.

1. Send and receive a test SMS to and from an Android user.
2. Send and receive a test SMS to and from an iPhone user.
3. Dump-text your group messages. Do a lot of quick-succession messaging within a 30-minute period with three or more members. This retrains the servers, especially on iPhones, to send SMS/MMS to your number instead of RCS or iMessage.

Step 5: Inform your contacts

Let your frequent contacts know:

• You have switched to a different phone.
• Old group chats may need to be recreated.
• Messages should go through, but may take a few days to stabilise.

Step 6: Wait the full 30-day period

After disabling RCS you must wait up to 30 days for deactivation to fully complete.

• Days 1 to 7: messages may be spotty as systems transition.
• Days 7 to 21: most messages should work, but some contacts may still have issues.
• Days 21 to 30: nearly all messages should work correctly.
• Days 29 to 30: many users report complete resolution.

Be patient. Do not conclude you have a problem until after the 30-day period is complete.

Part 2: Troubleshooting

Use this section if you have already switched phones and are experiencing problems, or if you completed the setup steps but still have issues after 30 days.

Understanding common issues

Messages go to individual texts instead of group. Your device is sending SMS instead of MMS. Check your group messaging settings in Step 3 of Part 1.

MMS timeout or temporary blocking. Some carriers temporarily block MMS after high volume in a short period. This typically resolves in 10 to 30 minutes. Reprovisioning your line can prevent future occurrences.

Why some groups work and others do not. Messages travel along the track they are accustomed to. New group combinations usually work fine, but recreating an old group with the same members often fails because the messaging system remembers the old protocol. The only solution is complete deletion and a fresh start.

eSIM-specific issues, missing MMS and media messages. Some eSIM users report that regular SMS works fine but MMS containing photos, videos or group texts is occasionally missed. This appears related to how some carriers provision MMS data access for eSIM devices. Try the following:

• Verify mobile data is enabled, since it is absolutely required for MMS.
• Check your APN settings match your carrier's requirements.
• Contact your carrier to verify MMS is properly provisioned for your eSIM.
• Ask them to refresh your network profile.
• Try an eSIM deactivation and reactivation cycle.

Technical note: MMS uses cellular data, not SMS channels. Even if SMS works perfectly, MMS can fail if the data connection or APN settings are not configured correctly. This is more common with eSIM than physical SIM, because some carriers use different provisioning paths for each.

Other people's phones have your number stored as iMessage. Even after your number is fully deregistered, individual contacts' iPhones may still have it cached as an iMessage address. The problem is on their end, not yours. Ask them to delete the existing conversation thread with you, then start a brand new message to your phone number, typed fresh rather than from the old thread.

Issue 1: Already switched without disabling iMessage or RCS

If you have already removed your SIM, you will need to temporarily put it back.

iPhone users with a physical SIM

1. Power down both phones.
2. Move the SIM back to the iPhone and power it on.
3. Go to Settings > Apps > Messages and turn off iMessage.
4. Go to Settings > Apps > FaceTime and turn off FaceTime.
5. Go to Settings > Apps > Messages > RCS Messaging and turn it off.
6. Visit selfsolve.apple.com/deregister-imessage and complete online deregistration.
7. Power down the iPhone, move the SIM back to the new phone, and power it on.

iPhone users with an eSIM

1. Log into your carrier's website or app and deactivate the eSIM on your new phone.
2. Wait 2 to 5 minutes for deactivation to process.
3. Reactivate the eSIM on your iPhone and wait for it to connect.
4. Turn off iMessage, FaceTime and RCS Messaging as above.
5. Complete online deregistration at selfsolve.apple.com/deregister-imessage.
6. Wait at least 24 hours, ideally 48 to 72, for full deregistration.
7. Log back into your carrier account, deactivate the eSIM on the iPhone, and reactivate it on your new phone.

Android users without the original phone

1. Visit messages.google.com/disable-chat.
2. Use the option for deregistering without the device.
3. Complete verification.
4. Wait up to 30 days for full deactivation.

Android users with a physical SIM

1. Power down both phones.
2. Move the SIM back to the Android phone and power it on.
3. Wait for it to fully connect to the network.
4. Follow Step 1 for Android in Part 1.

Android users with an eSIM

1. Log into your carrier's website or app and deactivate the eSIM on your new phone.
2. Wait 2 to 5 minutes.
3. Reactivate the eSIM on your Android phone and wait for it to connect.
4. Follow Step 1 for Android in Part 1.

Issue 2: Group texts not working

Once a group chat is established as fully iMessage or RCS, it stays that way. Old group chats often cannot be converted and must be recreated.

Solution 1, verify your phone settings. Make sure group messaging is configured correctly, as described in Step 3 of Part 1.

Solution 2, dump-text the group chat. Have three or more members do a lot of quick-succession messaging within a 30-minute period. This re-educates other phones that your number only supports SMS/MMS. It can take a few hours to a few days to work.

Solution 3, phone-number-only contacts. Ask all group members to remove any contact information besides your phone number from your contact card, including email.

Solution 4, clean-slate group chat. Ask all group members to remove group names and group photos, then send and receive a test message. If that does not work, back up and delete all chat history, then test again.

Solution 5, create new group chats. Ask someone to create a brand new group chat with the same members. If that does not work, try adding or removing one person to create a different combination. In some cases, having just one group recreate and re-send messages has resolved delivery issues in other group chats simultaneously.

Solution 6, the RCS toggle workaround. For group chats that remain stuck in iMessage even after deleting threads and waiting the full deregistration period, temporarily re-enable RCS while keeping iMessage off. Wait one to two days. Stuck chats should begin resolving and you may receive a backlog. Leave RCS enabled for one to two weeks to stabilise, then disable it again. A 30-day reregistration period may apply.

Issue 3: Still not working after 30+ days

If you completed all setup steps and waited more than 30 days, the problem is likely carrier-related.

Solution 1, phone-number-only contacts. Ask the other person to remove all contact information besides your phone number from your contact card, including email.

Solution 2, request carrier reprovisioning. Ask your carrier to reprovision or refresh your line, confirm SMS and MMS are enabled, remove any RCS or iMessage flags from your account, and update the text profile.

Solution 3, physical SIM to eSIM swap. On some carriers, switching from a physical SIM to eSIM or vice versa forces a full backend reprovision. Often works immediately, but may be temporary and recur in one to three weeks.

Solution 4, MMS blocking toggle. Log into your carrier account online, find the setting to block picture and video messaging, toggle it on, wait one to two minutes, toggle it back off, then restart your phone.

Solution 5, Verizon-specific steps. Contact Tier 2 Technical Support and request that they switch the SIM to CDMA-less status, disable Enabled Address Book, disable Verizon Messaging, disable Video Calling, and verify the SIM is not locked to another device.

Solution 6, test with a new number. Get a cheap temporary number and test messaging with it. If it works immediately, your original number has provisioning issues.

Solution 7, switch carriers (last resort). Multiple users report that switching carriers completely resolved persistent issues. Mint Mobile is frequently reported as a problem carrier for this process.

Issue 4: Additional troubleshooting

Try these in order if the standard solutions do not work.

Clear the messaging app cache and data. Many users report this fixes Not sent, tap to try again errors. Go to Settings > Apps > Messages > Storage, tap Clear Cache, then Clear Data, which deletes local message history, and restart the phone.

Check messaging app permissions. Verify your messaging app has location permission, storage permission for MMS attachments, and phone and SMS permissions.

Reset network settings. This erases Wi-Fi passwords, VPN settings and cellular configurations. On iPhone: Settings > General > Transfer or Reset > Reset > Reset Network Settings. On Android: Settings > General management > Reset > Reset network settings.

Switch default messaging app. If your phone has multiple messaging apps, try switching the default and then switching back. This can reset stuck configurations.

Factory reset (last resort). Multiple users report factory resets resolved persistent messaging issues. Before resetting, back up all data, contacts and photos, save all account passwords, and remove Google and Apple accounts from the device.

Additional resources

Fixing RCS and iMessage for dumbphones, a video walkthrough.