Occasional Green Bubble in Messages

Sometimes I get a green bubble when sending a text via Messages to a person with an Apple device.

An Apple Support article indicates that “An unexpected green message bubble” can occur when “iMessage is temporarily unavailable on your device or on your recipient’s device.”

Can anyone comment what would cause iMessage to be “temporarily unavailable”:

  1. Does this unavailability refer Apple’s service or the users’ device connectivity? (Presumably each user’s connection can be either WiFi, cellular, or wired.)
  2. Regarding user connectivity, does this refer to TCP/IP alone or is an SMS/MMS connection sufficient?
  3. Regarding wireless—either WiFi or cellular —connectivity, is availability affected by whether either the sender or intended recipient has cellular data turned on or off? (Isn’t SMS/MMS transmitted on its own channel—separate from voice and data—so isn’t signal strength—the number of cellular service bars—the sole determinant for connectivity?)
  4. The whole issue of iMessage being “temporarily unavailable” really baffles me. Isn’t it a store-and-forward protocol like SMTP? If not, then what causes a blue bubble with “message not delivered” below it?

Thank you for your input.

I get this as well and it is almost always when the recipient is out of range of WiFi and mobile service (eg, they are camping, driving in a rural area, etc.) or have their phone turned off. Sometimes it happens when I’m in a poor reception area.

You can sort of control this by turning off settings / messages / send as sms - this is for your sent messages. For sent messages, that way I am fairly certain that iMessage will, in fact, wait for the recipient to come back online and reactivate iMessage. But the way that messages works with that option turned on is to wait a short while to try using iMessage but then fall back on SMS (and show your sent message as a green bubble.)


I used to see this when we had data caps on our mobile plans. At that time, we limited our child’s cellular data to 5GB per month, in order to avoid overage charges. So she typically disabled cellular data except when absolutely necessary.

The result was that whenever she was away from a Wi-Fi connection, she would lose iMessage. Messages sent to/from her at this time would go as SMS. iMessage would resume when her data connectivity resumed (typically when at home or work, where Wi-Fi was available).

As far as I can tell, both. Apple’s service rarely goes down, but if it does, I would assume that it automatically falls back to SMS.

iMessage is an Internet feature. It requires an IP connection to Apple’s servers. If all you have is an SMS connection, your messages will go out as SMS, not iMessage.

iMessage requires a data connection to the Internet, whether that is Wi-Fi or cellular. If you have a cellular connection without data (e.g. no Wi-Fi, cellular data disabled or perhaps after hitting a data cap), then messages will fall back to SMS.

I’m not sure about this.

If the sender has no data connectivity, then it will (I think) automatically go out as SMS.

If the sender has data connectivity, but the iMessage server is down, I think your phone will hold the message for a while and will (if too much time elapses) fall back to SMS. I think you can long-press on an undelivered message to force it into SMS if you don’t want to wait that long.

If the recipient has no data connectivity, I’ve seen similar behavior - falling back to SMS after a long delay, with you having the option to force it to go out as SMS. I don’t know if the message is being held by Apple’s servers during this time or if it’s the sender’s phone periodically re-attempting to send the message.

If the recipient is logged on to iMessage from multiple locations and only some have network capability, it will be immediately delivered to those that are connected, and the other devices will see them later when they connect to the network. For example if someone sends me a message when I’m away from home, it immediately appears on my iPhone, and it appears on my iPod when it connects to Wi-Fi (usually when I get home). Which strongly implies that Apple’s server is holding the messages for some amount of time.


This is my experience too.

As David C. wrote, if there isn’t an IP connection, it’s going to fall back to SMS.

If you’re curious about all that happens behinds the scenes to deliver an iMessage, check out this section in the Platform Security Guide. The answer to any particular “unavailable” situation is going to vary.

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I think it’s something really simple.

That particular person has iMessage turned off.

I have friend with an iphoneand 2 iPads. All my messages to him are green.

He refuses to switch on iMessage.