When someone blocks your number, you usually get no standard message, but rather signs like calls going straight to voicemail (after one ring on iPhone) or texts showing "Not Delivered," though these can also mean Do Not Disturb is on; the key is consistency across calls/texts and lack of delivery notifications, sometimes accompanied by carrier messages like "unavailable".
One of the quickest ways to know if someone has blocked your number is to call them. If your call goes to voicemail after one ring, this could be a sign that your number has been blocked. But, no need to panic just yet. It's also possible that the recipient's phone is just turned off or in airplane mode.
Signs you may have been blocked
If you have an iPhone and text another iPhone but don't see a “Delivered” notification, someone may have blocked you. (Android phones don't automatically show these messages.) The same goes for if you consistently see a green text bubble instead of a blue one on your iPhone.
You can suspect someone blocked you on an iPhone if calls go straight to voicemail (maybe after one ring) and iMessages don't show "Delivered" or "Read" receipts, but these signs can also mean their phone is off; the most reliable test is trying to call them using a different number or *67 to hide your caller ID, and if it rings normally on their end but goes to voicemail from your real number, you're likely blocked.
If you have been blocked by someone on Android, then it is likely that you would want to text them. Unfortunately, since you have been blocked, there is no way to get your texts delivered.
When you text someone who blocked you, the message generally sends from your end but is blocked from reaching the recipient; you typically won't get an error message, but you won't see a "Delivered" notification (on iPhones, it might stay blue but lack delivery confirmation, while on Android, it might show "Not Delivered" or just hang, but you can't know for sure without them telling you or trying other methods like calls to voicemail or different apps).
If the person you're calling has blocked anonymous calls, *67 won't work either. While *67 hides your number from the person you're calling, phone companies can still trace the call. The good news is that using *67 is completely free, but you will need to dial it every time you want to keep your number private.
If you're blocked by someone, your calls will go straight to voicemail, and your voicemail messages will head to the “Blocked” section immediately. The other person won't receive your calls, won't be notified you called, and won't see a badge for your voicemail.
Muting helps you ignore someone without preventing them from doing anything. Blocking someone prevents them from messaging you, commenting on your observations, identifying your observations, and otherwise interacting with you on iNaturalist.
Check the chat bubble color
This is only true if both of you use iMessage on iPhones. This isn't a foolproof method. You may see a green bubble in the following situations: If the other person switched to an Android phone, their bubble may have turned green.
Signs someone has blocked your number
If you see a green bubble when you text someone, they may have blocked you, but bubbles can also turn green if you or the person you're texting are not connected to the internet, their phone is off or on airplane mode, or one of you has turned off iMessage.
It depends on your end goal. If you are doing this to get them back then just ignore. If you just want to move on then block. If your goal is to hurt them, I would advise not to.
An easy way of knowing you've been blocked is to send a message with read receipts on. If the message doesn't say delivered that means you're blocked. Calling is slightly different, it rings a couple times and goes to voicemail. You can leave a message which they will get but they won't receive a notification for it.
It's not always easy to tell when you've been blocked, but here are a few common signs: Your calls go straight to voicemail repeatedly. You hear a single ring before disconnection. Text messages show as “sent” but never “delivered.”
The person you blocked will not realize you blocked them when they try to call you. On their end, they'll hear the phone ring a few times. Then, their call will go straight to voicemail.
Practical signs someone may have muted you
Messages remain “sent” or “delivered” but never get quick replies: If your messages consistently show delivered but the person doesn't reply for long stretches while they remain active elsewhere, muting could be the reason.
However, the big distinction is that, unlike with a Block, Ignore will still let them see your profile and activity and allow them to send you messages (which you won't know about unless you unhide them).
If you're not blocked, the phone should ring anywhere from three to twelve times before going to voicemail. A blocked number may ring only once and then go to voicemail. (NOTE: It's also possible that the person is on another call, has their phone turned off, has a low battery, or has it set to airplane mode.)
If a person blocks you on iMessage, then they won't get any of your texts at all.
You can also use *82 to unblock your number in case your call gets rejected temporarily.
Method 1: Using caller ID restriction. Method 2: contacting through a different phone number. Method 3: Sending text messages or emails.