Troubleshooting Apple’s Junk Mail Filter

Last Updated: Sep 23, 2020

Written by

Spam filters are a necessary evil and it’s annoying when they don’t work as expected. Apple offers junk mail filtering in Apple Mail as well as via Unfortunately those two filters are not related to each other and thus can cause troubles and frustration.

Apple Mail’s Junk Mail Filter

Apple Mail has a built-in spam filter that you can enable or disable via Mail’s Preferences. Unfortunately, Apple Mail’s spam filtering capabilities are somewhat unreliable and I recently decided to disable it, in favor of a 3rd party solution.

Apple Mail: Junk Mail Preferences
Apple Mail: Junk Mail Preferences

I heard a lot of good things about SpamSieve and decided to give it a try. After the installation, I configured SpamSieve to move all messages, identified as spam, into a separate folder called ‘Spam‘, instead of Apple Mail’s default ‘Junk‘ folder.

iCloud’s Junk Mail Filter

I was positively surprised by SpamSieve’s performance but noticed that certain messages, some of which weren’t spam, still ended up in the old ‘Junk’ mailbox. I double-checked all my Macs to make sure none had the native junk mail filter enabled.

Puzzled by how that could happen, I contacted Apple Support via Twitter and they responded that iCloud also does junk mail filtering on the backend. They also indicated that, unfortunately, that backend filter cannot be turned off.

Apple Mail: Junk mailbox
Despite Junk mail filtering disables, messages are still placed into Junk mailbox

So I called iCloud Support to find out more about this backend filter and to learn how it can at least be trained. It turned out, that the front-end (Apple Mail) and backend (iCloud) filters work completely independently from each other.

In other words, marking a message as “good” in Apple Mail may still lead to the backend filter marking it as junk and vice-versa.

Apple Support re Junk mail filter

That kind of renders the filter in Apple Mail useless. The only way to train the backend filter is via the Mail app in There you can mark messages as Junk or Not Junk and hope that iCloud learns from that. Junk Mail Filter Junk Mail Filter

That’s a major inconvenience – I don’t want to open a browser and go to just to mark a message as Junk. That should really be functionality baked into Apple Mail. The worst part however is, that the backend filter cannot be disabled at all.

I’m hoping that the next version of OS X will allow Apple Mail to play more nicely with its iCloud backend service. That includes keeping rules as well as junk mail settings in sync across all devices.

Update [September 2019]

Apple is about to release macOS 10.15 Catalina and based on what I’ve seen in the betas, the junk mail filter in still doesn’t integrate with iCloud.

Even worse, since yesterday (9/20/2019), I’ve noticed that most of my emails end up in my Junk mail folder. The good news is there are two workarounds to this issue:

  • Use tools like SpamSieve to automatically recover those incorrectly flagged emails and put them back into your inbox.
  • Use SaneBox* — that’s what I use. It works similar to SpamSieve but it’s a cloud service instead of a plugin. That means, it can process my emails even when my Mac is not running.

Is Apple Deleting your Emails?

In 2013 I read on Macworld that Apple is silently discarding emails that contain certain, potentially offensive, keywords.

Two years later, in March of 2015, I was expecting an email from a contractor with a mockup of our future kitchen. But that email never arrived. We exchanged a number of text messages to make sure he had my correct email address. Unfortunately, no matter what we tried that email wouldn’t come through.

The funny thing was that the sender never got a bounce notification into his Gmail mailbox.

So I asked the contractor to send the email to my work address and within seconds it arrived. I don’t know exactly what happened back then but I can only assume iCloud silently discarded this email as spam.

When I called iCloud Support the other day, I reported this old case and submitted message headers and the original email to Apple’s engineers. Interestingly enough, the Senior Apple Support Engineer confirmed that Apple is discarding emails that come from known offenders.

While I like the idea of having a junk mail filter that operates with as little intervention from my side as possible, it cannot be that Apple discards emails that are clearly not junk without notifying the sender or recipient.

What do you think?

31 thoughts on “Troubleshooting Apple’s Junk Mail Filter”

  1. Hey, I was looking for useful information on iMac and just came across your blog and found it quite interesting, can’t wait to see your new post. You’ve been sharing really insightful posts and I’m an avid reader of your posts. Keep sharing the knowledge and adding value to our lives.

  2. Thank your for this information. It has been driving me mad….
    Have you had a chance to see if there is a work-around in the new BigSur version of Mail?

  3. Hi Michael, thank you for this article!

    I used an iCloud email in the past but it also happened to me to not receive some emails (for instance from IFTTT). I contacted Apple Support, got someone on the phone who told me 1) it’s due to a server side filtering 2) even him cannot recover the deleted emails because he has no way to see which emails were deleted! It’s a completely “silent” process, and to me this is a major design flaw in iCloud Mail.

    I switched to another email provider solely for this reason, and so far my exodus is far from ideal:
    – I tried Microsoft Exchange (via Office 365) but there are many settings to fine tune and it’s kind of nightmarish and overkilling. But *at least* the anti-spam was good
    – I also tried FastMail but their anti-spam is also really bad: they ask you to train 200 false negative *and* 200 false positive before firing up a personalized filtering algorithm. At the current rate, I will take me something like *three years* to get a personalized filter…

    So far only Gmail and Microsoft have been able in my experience to deliver decent anti-spam filters.

  4. seriously thinking about installing ‘outlook’ on my macs. that’s how poor the mac mail app is now. I am billed for my electricity by email, & frequently find the emails in one of the six or seven ‘junk’ folders the app has now spawned, with no way to mark it as ‘not junk’ (though I read somewhere that this option still exists via the browser-based mail viewer), even though the sender is in my contacts list. I’ve spent three hours today diagnosing an unrelated ‘security’ issue that arose after the last security update & prevented me sending emails from any of the three accounts on the machine. it’s all gone to shit since jobs died, I tell ya!

  5. When you create a rule to move junk mail to the junk mailbox and mark it as read, does it work for you? For me it absolutely doesn’t. They go to the junk mailbox but appear all as unread, which gives me the hives. Is there anything I can do to fix it?

  6. Someone who knows what on earth is going on! I just signed onto a new device (Apple Desktop) and now ALL emails going back to April of this year (random!) to anything now go to junk. I changed the settings on my laptop but nowhere to change them on my iPhone. Grrrr. I also have a bizarre problem with my Apple ID that absolutely no one at Apple (on phone or store) has been able to figure out. Do you do consultation work with clients locally? I am in Atlanta too. I’ll pay you if you could fix this!!

  7. I just watched 3 mails appear on my macbook and be gone immediately, at least two were from slack, business related. They are nowhere to be found, not in trash not in spam. Gone on every gadget.
    The same thing happened a few months ago with LinkedIn. I’m not even sure, that it is the backend filter, as the messages are visible for split seconds.

    • Hi Helga,

      that’s odd – I’ve never seen that before. If it’s the backend, you shouldn’t even see the email as it would get filtered before it reaches your inbox. It’s got to be something on your endpoint that causing this.

      • Ours is the opposite. All mail is going to junk – all of it, despite trying all the troubleshooting we’ve found. On the Mac desktop, we can move an email from junk to new, and then read it, and it stays in new on all devices (Mac desktop and laptops, iPhone and iPad). But if we’re using one of the iOS devices and move an email from junk to new, it’s also visible for a split-second but then disappears for good – on ALL devices, never to be seen again. Still working on it.

  8. Using the Mail app, my Mac is unable to receive a couple of email IDs that show up just fine on my iPhone and iPad. Junk Mail Filtering is enabled, but set to “Mark as junk mail, but leave it in my inbox.” Mail from those problem IDs, however, doesn’t appear in either the inbox or junk folder, even though it shows up on the iPhone & iPad. That means it can’t be iCloud filtering and must be specific to the Mac. I also use Rules to automatically delete suspicious emails from domains in other countries (.ru, .it, etc.). In the Mail app, when I searched for one of the problem IDs, I got a dozen or so matches, but they were all from 2014 or earlier. There must be some file, probably a hidden file, that contains these problem IDs and blocks them. I tried using Finder to search, including hidden files, for one of the problem IDs, but there was no hit at all. I might just ignore this if it were just a friend, telling him to send to my wife’s ID and having her forward his email to me. But now I find that one of the problem IDs is used as an alert from my bank. Missing an important alert could be serious, because I rarely check email on my phone. I’m out of ideas and hope someone can help.

  9. I have been going to iCloud to let it know that certain messages are not junk for about 6 months now. (My Mac client app has junk filtering disabled.) The iCloud backend continues to send them to the junk folder. The backend is not learning. I think I’ve observed a pattern, though. The mail which keeps getting mislabeled false-positive as junk is consistently politically conservative.

    • I’m seeing the same … mail with address in my Contacts and from “conservative” sources, e.g. Washington Examiner, are consistely “junked” by Apple mail.

  10. Apple’s junk filter is crap. You can designate a given sender as junk 50 times and Mail will still not get the hint the 51st time.

  11. Thank you for your blog post, that helped me feel less frustrated, as this morning I opened my email app and it said I had 45 incoming emails. Then they all just disappeared. I then found them all in my Junk mail filter. Over half was normal mail that had never been shoved to the junk mail filter, even emails that I and my son’s teacher had been writing each other. So I initially missed a scheduled meeting the school wanted to have this coming Wednesday. Very glad I checked. And like many others stated, messages that are clearly spam seem to get through to the inbox anyway. I’ve rarely, if ever, had those problems on hotmail or gmail, especially not in the past 5+ years that I can recall. I’m an Apple product junkie and have been since 2005.

  12. I have set up the filter to have Mail delete anything containing, but they still get through.

  13. Clearly, Apple is deleting messages originating from Gmail accounts or filing them as junk as a sly way of sabotaging Android users and taking a dig at their biggest competitor, Google, inc. The way the filter works is a deliberate, pestilential misfeature and given the way Apple operates, it is not likely to get fixed in the foreseeable future. The best immediate solution for the user is to take a 3-pound sledge hammer to all of one’s Apple devices. The best way of getting Apple’s attention is to stop buying their products.

  14. >>That’s a major inconvenience – I don’t want
    >>to open a browser and go to just
    >>to mark a message as Junk

    This is incorrect, you can sync the Junk Mail folder in the Mail app with the iCloud Junk Mail folder.

    • Hi Steve,

      Unfortunately, keeping the folder in synch does not necessarily mean your junk mail training data is kept in sync as well, which is what I am describing in the paragraph you are referencing. In fact, right before I said: “The only way to train the backend filter is via the Mail app in” That is still true as far as I know, regardless of how and where you store your junk mail folder.

  15. I dont want a junk mail filter-BUT disabling it within Preferences makes no difference – I want everything in my IN box MAIL 11.2, High Sierra 10.13.3

  16. I hoped I was going to find some tips here to help me debug why a OS X Mail filter (not junk-related) that has worked for years and has never been changed suddenly stopped working, despite the fact that an eyeball review of the filter and the incoming messages indicate that there is no reason the filter shouldn’t still be operating on them.

  17. Thx a lot for your information. I tried hard to solve problem as well. Just ridiculous, it’s not a simple move to button, I am deciding. So many cannot be moved, so many rubbishy still are coming though marked already more than once. Apple shouldn’t work on big shows to release nothingatallnew phones without looking into simple user related basics. Spending lots of time – no solution!!!

  18. Thanks. I thought I was going crazy. I must have turned the mail filter off 10 times and still things were filtered to a spam folder. I kept missing emails because they were not showing up where they were suppose to be. I end up having to dig down through the multi stage of email boxes to find the good emails in those folders. I find that most them are from gmail accounts.

  19. This is so frustrating!! Messages which are so blatantly obviously junk come into my iCloud inbox instead of going into the junk folder. Apple should be embarrassed that in 2017 they can’t get something as simple as a junkmail filter to work as intended! I’m using iOS 10.2 on my iPhone.

  20. Thank you for the clear explanation of a number of mysteries about the junk filtering. I hope Apple will get its act together on this.


Leave a Comment