I keep getting messages with different From but the same mailed-by field. I need to mark these messages as spam, but simply doing so doesn't work.

Creating filters searches for From values only, so that doesn't work either. How can I mark these messages as spam/ blacklist them by the mailed-by value?

  • 1
    Filter or no, keep do reporting them as spam so Gmail's spam filters can learn.
    – ale
    Commented Feb 12, 2014 at 15:35
  • 1
    Can you post an example set of headers? There might be something you can do with the "contains" filter.
    – ale
    Commented Feb 12, 2014 at 15:35
  • "Creating filters searches for From values only" This is patently untrue. There are a lot of things you can use as a filter. The From: field is only one of them.
    – ale
    Commented Feb 12, 2014 at 20:14
  • mailed-by isn't a header field, but if you can figure out one to key off of, you can use the info from this question: Is it possible to create a Gmail filter that works on headers other than From, To, Subject?
    – phantom42
    Commented Feb 12, 2014 at 20:49
  • Add a screen shot of what you call mailed by. Tag me then.
    – user105815
    Commented Jan 11, 2016 at 6:56

2 Answers 2


Unfortunately not. According to the Gmail Help page Search operators you can use with Gmail, there is no filter for mailed-by. If you can find a common link between the emails being sent, you can filter using these search operators and then create a filter to delete them.

If not, there are suggestions from Gmail as to how to act on these emails. As you can see, some of these are not ideal or even practical, but it seems to be the only way at this point:

A message I received wasn't authenticated

If a message you get from a trusted source isn't authenticated, contact the person or company who sent you the email. When you contact them, provide a link to this help page so they can learn how to authenticate their messages.

Source: Check if your Gmail message is authenticated

The message seems suspicious

If you aren't sure the message was sent by the Gmail address you see, follow these steps.

  1. In the warning message, click Report phishing.
  2. Do not provide any personal information or click any links in the email.

Source: This message may not have been sent by...

Mark or unmark Spam in Gmail

The more you report spam, the better Gmail gets at automatically marking similar messages as spam.

  1. Open Gmail.
  2. Select one or more emails.
  3. Click Report spam Report spam.

Source: Mark or unmark Spam in Gmail


For whatever reason, there is no way to filter by mailed-by at this point in time. However, Gmail can do something about it. Unless you can find another common link between the emails, reporting the messages as Spam and Phishing is the most practical way to stop them from appearing, although the effects will not be immediate.


I believe the Spam function is just a filter to filter out what you mark as Spam, it does not permanently block emails coming back which are marked as Spam nor does it delete them.

One way round this is:

  1. Set a filter to delete the emails
  2. If it still not enough then get a new email address and don't register on too forms and be careful who has your email address online and offline

Also look into private email clients such as Outlook and look up block email by IP ref - Google Search: block email ip

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