Mail not working on iPhone after iOS 18 Update

I tried the "/" fix but this didn't work for me.

I noted some folks tried different client apps other than Mail.

Gmail got the same error but MS Outlook worked fine so I am using that without any problems.

iPhone on 18.1.1

All recommendations in this thread didn't work for me. However, surprisingly, when I reduced the number of emails in my Inbox, it works as expected. I'm not sure what is the maximum number of emails in Inbox but it worked when the number is 1,300.

@sjcorpst - I have that issue from time to time also! Then, later that day or the next day the body of the messages are there! But, I cannot respond to a message or create a new message and send it from that email account.

I can’t add any more email address to my iPhone it’s gone, there is icon to email accounts. WTF is wrong with Apple? This is unexpected and it’s insane as I have 3 addresses and now I can’t add them and have you use my laptop to access my other accounts. Fix this Apple..asap. How could this get by everyone on the last update? Where is the mail icon under general in setting????!

Suddenly, Outlook for Mac is working like a champ. I haven't done anything new, only the same things everybody else has done. I'm still not having consistent luck on my iPhone or iPad using both Apple Mail and Outlook.

I'm wondering if this has to do with the age/version of the device. I have an iPhone XS and my wife has an 11Pro and we have no problem with the Apple Mail app since iOS 18.1. Maybe it is just the newer devices that are having this issue? I'm also not having a problem with my 3 or 4 year old iPad Air.

Note: I just updated to 18.2 and Apple has added some 'features' to the Mail app, none of which I want or need, but others may like them. I turned them all off.

1) Delete the account

2) shut down the phone

3) start phone

4) add account (again)

send and receive should now flow.

Took five times but eventually it worked let’s see if it lasts usually when Apple ignores multiple requests for a problem they feel like they’ve solved it already but still it’s hard to find concrete results. What I listed above worked totally fine and I literally updated the patch this morning, hoping it would fix things, but it didn’t so I did the above steps one more time and had success.

Try to reduce the number of mails in your mailbox. For me, only two mail folders including Inbox and Sent Messages kept failing to be synchronized with my IMAP server. After moving mails in my Inbox to the other folders on macOS mail client, it began to work properly. Sent Messages which has 11,258 emails is still suffering synchronization problem. On the other hand, a mail box which has 4,950 mails is synchronized without problem. I think it' worth trying.

I have an iPhone 16 Pro and iOS 18 (18.1.1 to be exact) and was having the problem of my Mail not syncing between devices. This suggested fix took care of that issue. I’m not on a business server; I’m a standard client on Comcast.

What I find is that mail in iOS 18 is extremely slow to sync with the server. I can pull up outlook at the same time mail is struggling to connect and see messages that ultimately appear in mail way faster with outlook. I am on iOS 18.2. Can Apple finally take this issue seriously and address the performance problem in their mail application?

Try using webmail to check your imap server settings.

In webmail account settings it should tell you things about the server setup. These need to match your iOS Mail settings.

Also your email service provider should be ensuring that with each iOS release their imap servers are tested & compliant. With the billions of iPhones out there being tested & compliant to the most used mobile email client is a must do.

Ever since they did 18.2 update mail does not show up unless you hit one of the new tabs they put in the email folder it’s very frustrating as when you look at the app it shows no mail you have to go into each account and hit the tab for mail to show up.

When is Apple going to fix mail in ios18 it’s very frustrating. Had to wait until I can go on my computer to get mail. Even the mail app on my computer says no content in the message but it’s there on my iPhone

Yes, we know the mail is not working for thousand of people. I have no answer for that.

Your "view every account" issue is unrelated to this discussion, however I thought I'd post this as I think this will answer what I think the problem is you (and probably others) are having with the new iOS mail app (default) interface.

https://osxdaily.com/2024/12/16/disable-mail-categories-inbox-iphone/

I didn’t pay one 1k for a phone to have to do all the technical rubbish on here being suggested. It has gone belly up since that update it might be

pure coincidence but I find that hard to swallow quite frankly