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Emails Opened? Is There a Reliable Way to Tell?


In my business, it is critical I know that emails I have sent were received & opened. The emails are time sensitive and contain deadline dates for the information requested.

I have searched for things like “emails opened” and asked questions… but all that has been futile.

I am certain I am not the only person unable to find an answer to this problem.

That’s because there is no answer to this problem.

And you’re quite right, you’re not the only person wishing otherwise.

But wishing – or even the statements of some companies that claim to be able to do it – doesn’t make it so.

I’ll explain why.

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Emails opened: the bottom line

I want to start by making this very clear: there is no 100% reliable way to tell with certainty that an email you send has, or has not, been received, opened, or read.


If your business relies on that, then you need to investigate alternative approaches to communicate with your target clientele.

I often get a lot of push-back when I make those statements, but that’s the way it is. There’s no magic tool or technique that can make it otherwise.

Why you can’t tell

There are a couple of conceptual reasons for this, and you can choose one or the other, depending on your cynicism:

  • Email is broken.
  • Your recipient’s right to privacy trumps your need to know.

We can argue about the first all you want, but it’s really that second that says it all.

It’s spam that made everyone realize just how important that last one is. Spam is the reason email programs disable the mechanisms that could be used to track email reception.

So you can blame spam, if you like, for making this impossible. Whether that’s part of “Email is broken”, or “right to privacy”, it is what it is, and at the risk of repeating myself, it means you cannot reliably track with certainty whether or not a specific email has been opened or read.


Emails Opened?Traditional methods

There are two traditional methods to track whether or not an email has been received or opened.

1. Delivery and Read Receipts

Email protocol allows email messages to include a request for a “Delivery Receipt” and/or a “Read Receipt”.

The idea is that when the message is delivered to the inbox, the email program would automatically send a “delivery receipt” email back to the sender, saying, “it’s been delivered”.

Similarly, when the email is opened, the email program would automatically send a “Read Receipt” email back to the sender, saying, “it’s been opened”. (Whether someone actually read it is beyond the abilities of computer to know; all they can say is “it was opened and displayed on the screen”.)

Here’s the problem: most email programs no longer respond to delivery or read receipts, which means that the requests are completely ignored. You’ll get no notification, even if you ask for one. At best, the program may ask the recipient whether or not the receipt should be sent. Most recipients, of course, say “no”.

The reason is, as you might have guessed, spam. Spammers use receipts to validate that an email they’re sending to is a valid email address, and thus should be spammed even more.

No one wants that, so the feature is completely disabled by default.

2. Tracking Images or “Bugs”

In HTML or rich-text email, images can be included in email messages. Those images can be included with the message, or they can be fetched from some location on the internet in order to be displayed. A good example is The Ask Leo Newsletter. It includes at least two images: a logo at the top, and my signature at the bottom. The images themselves are not actually included in the email, but instead are references to images stored on an Ask Leo! web site.

I can tell when those images are referenced. When you open an email with those images, and have image display enabled, your email program makes a request of my web server to fetch those images for display. My web server can log that. In fact, it’s possible to include in that request not only the image desired, but also the email address of the recipient of the message that needs the image (I do not).

In other words, it sounds like a perfect tracking mechanism to determine whether an email has been opened or not. . .

. . . which is why spammers started doing exactly that. To determine whether or not an email address was valid, they would send a message with an image and some additional information unique to that email address. If the image was ever fetched, that told the spammer they had a valid email address with a real person who looked at it, and thus deserved more spam.

And that, in turn, is why email programs no longer display images by default. If image display is disabled, then the entire approach to tracking via image references fails completely.

Email open tracking services

As I said, I get push back from individuals or services who provide open and delivery tracking services, telling me that their service is special – their service works.

The techniques they use fall into two buckets:

  • Image-open tracking, as I describe above,  may work for many recipients, but it simply cannot be relied upon to work for every recipient. Even a single recipient that refuses to display images invalidates the claim.
  • It’s not email. As I’ll describe in a moment, one technique is to move the message delivery away from the email infrastructure to some kind of private message delivery tool. Usually this is done by forcing the recipient to visit a specific web site if they want to get the message. This doesn’t track how many people got or opened the email; it only tracks the number of people willing to take the extra step to get the message.

Lack of data tells you nothing

For the record: most companies that offer to track email delivery and email opens use image references. Since many people do enable image display – typically for people they know and trust – it can still work – sort of. However:

  • If an image is referenced, then the email was displayed. Success? Not really. Just because it was displayed on someone’s screen doesn’t mean that it was actually read.
  • If an image was not referenced, then the email may have been lost, or ignored, or routed to a spam filter. Or it might have been read with image display turned off. There’s simply no way to know,

The technique is simply not 100% reliable.


The most common alternative boils down to using a private messaging system.

The technique works like this: you place your message on an on-line service of some sort – perhaps even your own web server – and then email a link to the message, instead of the message itself. In order to read your message, the recipient must click on the link and visit the web server holding the message. That visit can be reliably logged.

Exchange Server is another kind of private messaging system. People on an Exchange Server-based system (for instance, at a business) sending to others on that same system can often get reliable notification that email has been read or opened.

But if the email message can simply be read on its own, without requiring external resources – just by showing up in someone’s inbox – there’s just no way to know with 100% certainty whether or not the message was delivered, opened, read, or ignored completely.

How open tracking can still be valuable

As I mentioned, I have open tracking on The Ask Leo! Newsletter. You’re probably wondering why I do so, if it’s so unreliable?

It may be unreliable, but in general it’s consistent.

To begin with, I don’t care about specific opens. I can’t know with 100% certainty whether or not you’ve opened my newsletter. And that’s OK.

What I do care about is trends over time. If this week’s newsletter shows that 50% of the newsletters were opened (meaning that my logo and signature were displayed when someone opened the newsletter), and then next week that drops to 25%, I care about that. I care about that a lot, as a matter of fact.

This kind of aggregate trend over time is what open rates are really good for, and you’ll find that almost every newsletter you receive likely has some form enabled. We’re not looking at you, specifically, but we are looking how our subscribers, as a group, are reacting to what we provide. A sudden drop in open rates can mean many things, ranging from terribly uninteresting content to filters that have decided that email was spam.

What it does mean is that the sender needs to pay attention and address the issue.

And hopefully, from that we learn what you find most interesting and engaging, and more likely to be delivered to your inbox instead of your spam folder.

And that all leads to better newsletters for everyone. :-)

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35 comments on “Emails Opened? Is There a Reliable Way to Tell?”

  1. For those people who “blame” email for being so untrackable, remember that most paper mail doesn’t have reliable proof of reading, either. Yes you posted it, yes it was delivered, yes it was even signed for (by some illegible name) and even yes it was handed to the addressee. And she threw it straight in the bin because she didn’t realise how important it was, or it looked like junk mail. So the sender has “proof of delivery” but no-one read it! It’s not an email-specific problem.
    And just like paper mail, you can REASONABLY rely on the fact that IN MOST NORMAL CIRCUMSTANCES email IS delivered, and IS read. If it’s not deliverable you will be told. Yes, that system is probably not 100% good enough for military or even some business cases where it is really important but for most of our email it works. If you aren’t told anything to the contrary, it’s been delivered, and probably been read.
    One big exception is when you’ve sent an email to someone for the first time, and you’re not in their contacts/address book, and their over-zealous (IMO) email system has intercepted it. BT/Yahoo does that. And many of their customers don’t know that the intercepted email is put in a junkmail or bulk mail folder that can only be seen via Webmail access, and these same customers don’t remember being told about that (they were) and/or don’t know how to get into webmail, or where to look find out how.
    If Leo doesn’t agree with my general perceptions, I’m sure he’ll explain, below :o)
    And if he says I’m wrong, I’ll believe him. :o)

    About the only tweak I’d make to your thoughts is simply that it’s (sadly) not always safe to assume that email’s been delivered if you hear nothing. Many failures are silent these days, as are some of the many accidentally deliveries into the spam/junk folder. The vast majority of mail is delivered, yes, but it’s actually no longer safe to trust that “silence implies receipt”. If important, I’ll add to the message “let me know that you got this” for a manual confirmation that the email made it and was actually read.


    • The Spam collection is the one most people never check or don’t even know it exists or how to get to it.
      I have a friend that falls into the later category in spite of my attempts to train them.

      There is another group: Those who intended to send email, sent it to an old email address, or forgot to hit send and left it sitting in the drafts folder.
      The last of those is one I do occasionally.
      Person from first paragraph had two of the other reasons recently. Two people were rather irate about them not responding to their emails. As tech support, I searched their gmail account (which never deletes anything) and there was no messages from either of the people relating to the “unreturned” ones. Both regularly send the person emails to the proper address but there would be a slim chance of them using an address that ended 4 1/2 years ago. My best guess is that they thought about sending it (but didn’t actually write it) or having a surprise coming when they have a reason to look in their drafts folder.

  2. This is interesting. I have had a couple of times when signing up on a site or reseting a password, that the system sends an email request to verify its really me. After I reply, then it sends my needed info in a return email or lets me log on, etc. I.E. in their sent email include: please click on this link, follow instructions, etc. I would think this would be a way for this person to have some sort of verification if his/her email was verified it was received and read by someone wanting to read it… The idea is is you have to read the email to get the info you requested in the first place. What do you think leo?

    The issue is more about people who claim they never got a message, and yet did. People are (desperately) looking for a technology solution to prove that “yes you got it, and you opened it”. Sadly there’s no reliable way to do so.


  3. AOL has a ‘check status’ feature — but it works only with mail sent from one’s AOL account to another AOL account/email address.

    • My whole family and many friends are long time AOL users. The great “check status” feature works giving the actual time that the recipient open the sender’s email. How come this works only for AOL to AOL email?

      • It works because AOL controls the entire chain that the email uses. This is why it also works with Exchange servers for people inside a company.
        Once it leaves AOL’s system, other systems (for reasons explained in the article) will usually NOT tell AOL that it was opened. I can imagine (because of the amount of spam that AOL allowed in the past) that other systems would really not want to give any indication back to AOL.

  4. The comments here are kind of comical. It’s as if people didn’t even read the article. They saw what it was about and jumped right down to the comments section to endorse one system or another that claims to verify that an e-mail has been received and read, every one of those systems being an obvious variation on one of the two methods Leo wrote about above, stating very clearly why they’re not reliable.

  5. I’ve been using MailChimp for a year now to send mail to about 80 people I know. MailChimp offers extensive statistics including who opened it, clicked on it, etc.

    I noticed a very small percentage of opens, so I asked those who showed as unopened whether they’d received the email. They said they’d read it.

    My conclusion: many people read their mail in Preview mode. They rarely click on it to open it. I do this tooinOutlook 2013. Am I right that previewing an email does not count as an open?

  6. Status 2 worked great for several years. After a computer crash 4 or 5 years ago (think it waswin2k before crash–but the switched to XP. I was never able to get it back up and working. Their automated system created a loop that kept me from getting back online. Their tech support never responded even though I had the premium service MSGSTATUS2. Because order number, etc was on crashed hard drive I couldnt enter the info needed to get into their tech support I finaly made contact through a third party, a reviewer who ran a blog of some kind. My MSGSTATUS2 account was reset and it initially appeared I was back in business. But my outlook (oex no longer available) msgs were not tagged or at least never showed up on the Dashboard as they had before and my efforts to again get support seemed to have been ignored-or never received. After spending countless hours (much>24) I gave up and went to gmail that allowed an image based track system. I recently Installed an old 2003 version of office on my win7 pro system. I have wondered if I should try msgtag now that image based methods are no longer 100%. Would be interesting to see if msgtagstatus2 support has gotten more responsive.

  7. Message receipts is a Microsoft thing. There is a better email system than Exchange – Novell GroupWise. When you look at your sent items’ properties, you will see when your email is read and/or forwarded. This email system is much better than Exchange. They had this feature 15+ years ago. I doubt in my lifetime will Microsoft ever have these features built in.

  8. It may not be possible to tell for sure, but an idea just occurred to me. Write the message and convert it to a .jpg or .png file remotely linked to the email. That would ensure that the person has to open the image to view the email, and you would be sure they at least opened and likely read the email.

  9. Leo
    In the section on Open Tracking, you write:

    “A sudden drop in open rates can mean many things, ranging from terribly uninteresting content to filters that have decided that email was spam.
    What it does mean is that the sender needs to pay attention and address the issue.”

    In view of this, it’s noteworthy that when I click to open the Ask Leo? messages, my email client (Thunderbird, which we both use) tells me that it thinks the message is a scam.

  10. I work for a company that uses a marketing service-something like Constant Contact, but for their type of industry-for sending out newsletters, communications etc. The service analytics reports shows what emails were opened and which ones weren’t (perhaps the same type of technology Leo was discussing about his newsletters?). While this solution is impractical/inappropriate for daily communications, there’s no rule stating you have to send only newsletters or promos-you can send any email out, to as many or as few as you wish, with any content. Depending on what you’re emailing, it may be useful for some…?

    • The service I use – aweber – does the same. But these figures are NOT 100% accurate. They reflect only those emails which were opened with images enabled, or had links clicked within them. If a person opens an email without images enabled, reads it, and then discards it, there is NO WAY TO KNOW. Period.

      • Saying that this method isn’t 100% accurate seems like that’s giving too much credit. Since all modern email programs and most webmail interfaces block pictures by default, the accuracy would seem to be much closer to 0% than 100%.

        • It … varies. There’s a reason that most commercial newsletters say “enable images for the best experience”. Yes, it’s a better experience for the reader, but it also enabled open tracking as a side effect. (And when clicks on links in an email are also tracked, that implies an open as well.)

  11. There’s also a mail tracking tool not mentioned here – I’ve discovered it recently when I was looking for a free alternative to mailtrack, because I need to track a lot of emails monthly. I must say it works fine for me. This extension doesn’t have read notifications yet, hope they’ll do it.

    • Read notifications are notoriously unreliable. The receiving email program usually has a way to turn those off, and most people do just that.

      • And by default, most email programs and webmail interfaces block downloading remote content which is how emails are tracked. So unless the receiver explicitly turns it on or clicks on a link, there is no way of knowing if the email was opened or viewed.


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