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How to Avoid the SPAM Folder in 10 Easy Steps

The war against SPAM is on!

Internet Service Providers (ISPs) are waging an endless war against the spammers who invade our mailboxes.

This war has heavy casualties in the form of “false positives”—legitimate commercial emails mistakenly routed by spam filters to bulk folders.

If your marketing results suffer because you struggle to reach inbox space consistently, keep reading and learn 10 foolproof steps for avoiding the SPAM folder.

1. Avoid Purchased Lists

Have you ever been tempted to grow your list by a million potential customers in no time? Have you been to forums where thousands of “targeted leads” are sold for a few bucks?

Purchased lists are ticking time bombs, waiting to devastate your reputation as a sender. Riddled with dead emails and spam traps, they quickly inform mailbox providers that you break the rules by sending unsolicited emails.

At best, your messages may end up in junk folders. At worst, you may be branded as a spammer.

If you still buy emails lists, STOP NOW.

2. Watch What You Say

Spam filters analyze your content. There are no magic keywords to enhance deliverability, but limiting the use of risky words—such as free, buy, promo, etc.—reduces the likelihood of your emails landing in the spam folder.


  • Link only to legitimate sites with reputable domains.
  • Don’t go crazy with email size (30 kb is just fine.)
  • Balance the image-to-text ratio.
  • Host your images at credible services only.

3. Team Up With A Reliable ESP

Email Service Providers (ESP) are evaluated as senders based on the reputation of the Internet Protocol (IP) addresses and domains of their clients.

Careless ESPs with low scores on the IP addresses of their senders are destined for spam folder delivery. Eventually, they will be blocked by the providers like Gmail, Yahoo! Mail, and Hotmail.

ESPs that send only solicited emails and ban spammers from their platforms have greater credibility with mailbox providers. Their Customers are more likely to experience undisturbed inbox delivery if they follow the steps outlined in this post.

4. Get Certified!

If you are on a dedicated IP space, you should definitely look at the certification provided by a company called Return Path. Once they audit your mailing practices, you can get a Sender Score Certified status which will guarantee that you inbox at most of the major ISPs out there. This service is not free, but it definitely deserves a closer look. The money spent on the fees should be easily returned by the increased conversions.

5. Avoid Dirty Tricks

What may have been effective in 1997 no longer works today. Remember, being caught red-handed in any of these practices may cause permanent damage to your deliverability ratios:

  • Hashbusting: Inserting random characters in the subject line or content to fool spam filters, e.g. “F.ree. p.r!z.e”
  • Deceptive Subject Lines: Starting the subject line with “Re:” or “Fwd:” to suggest an ongoing communication with the sender.
  • Misleading Claims: Subject line stating that the recipient has won a prize, while the copy lists conditions that have to be met in order to claim it.
  • Image Text: Concealing a text message in an image to fool spam filters.

6. Whitelist Me, Please!

Your Email Marketing Service (EMS) asks mailbox providers, such as Gmail and Yahoo Mail, to whitelist your domain or Internet Protocol (IP) address. That is why it’s important to send marketing emails through a reputable EMS, rather then sending emails from your own email server or email account.

When confirming your new subscribers (e.g. via a welcome email), ask them to add your “From” address to their address books. It is a foolproof way to release all future emails from the constraints of the spam filters. This is so easy, yet practiced so rarely.

7. It Matters Where You’re “From”

Mailbox providers evaluate more than just the sender’s IP, domain and content. Yahoo! Mail, in particular, pays close attention to your From field addresses.

Our internal analysts have even noticed variations in deliverability results from using the address versus

  • Avoid frequent changes of From field names
  • Avoid obscure From field names, such as: “”, “”
  • Use clear, trustworthy From field names, such as: “contact@”, “newsletter@”, “support@”, feedback@”

Stick to a limited number of verified, recognizable From field names. Build a good reputation for those addresses by sending only engaging, solicited emails, and you’ll notice the difference.

8. No Risk, No Problem

Your email campaigns may contain risky elements that are detrimental to the deliverability of your messages. Here’s a brief checklist to go through before you hit the “Send” button:

  • Be careful with words associated with the language of sales. If overused, they may trigger spam filters and route your emails to junk folders. Risky words include: “prize”, “free”, “bonus”, “buy, “purchase”, “order” etc.
  • Common sense will tell you that one exclamation mark per sentence is enough. Never shout at your subscribers, (e.g. “Buy my e-book now!!!”). Exclamation marks are especially risky in email subject lines.
  • Never overdo the use of “ALL CAPS.” When emphasis is needed, use a maximum of one word per sentence in all capitals, never a whole sentence.

9. Monitor Your Deliverability

Want an easy way to monitor deliverability that costs you nothing? Add a “seeded” list of email addresses using ISPs that your customers use most often, such as Gmail, Yahoo Mail, AOL, and Hotmail.

Set up approximately 5 mailboxes at each provider then include the seed email addresses in your mailing list. After each newsletter is deployed, log in to each seed account and verify whether the email was delivered successfully by that provider. Pronto!

If you notice a deliverability problem, check your adherence to the other 9 points listed in this post. If you still experience problems, consult with your Email Marketing Service about how to resolve the problem.

10. Stay In Touch!

Sending emails once every two or three months can be more detrimental than sending multiple emails daily. Why? Your Customers might forget all about you.

If subscribers fail to recognize the From field, they may delete your message, hurting your “open” ratio. Even worse, they may forget signing up for your list and generate negative feedback by marking messages as spam.

There are lots of good reasons for maintaining a steady flow of communication, rather than relying on infrequent, massive “blasts.”


There are two golden rules in the world of email deliverability:

  • No ESP can solve your deliverability issues if you decide to purchase email lists.
  • Even the most beautiful email template can’t generate conversions if it lands in the spam folder.

Try out the tips mentioned in this post while reviewing your email program. Each of these steps can significantly increase your inbox placement rate and lead to more email conversions!

About the Author: Maciej Ossowski is Education Manager at GetResponse. GetResponse is an easy email marketing solution that serves over 210,000 email marketers and delivers 10 billion emails a year.


About Kissmetrics

Kissmetrics combines behavioral analytics with email automation. Our software tracks actions of your users across multiple devices allowing you to analyze, segment and engage your customers with automatic, behavior-based emails in one place. We call it Customer Engagement Automation. Get, keep and grow more customers with Kissmetrics.



  1. Great tips.

    I’m a little weary of the seeded email trick. Seems like a lot of work.

    I would say if you’re doing all the other suggestions, that step wouldn’t be necessary. I do send my email to the two email addresses that I already have.

    What do you think?


    • Brad,

      I think sometimes you get out a lot of what you put in.

      If you were changing or evaluating ESPs then I think this is a good tactic.

      Once you’re happy with performance you perhaps only need check once-in-a-while rather than after every send.

      However if your response rates take a nosedive, you already have something in place that you can check.

      Some ESPs like to think they perform better than they do on some email providers – having hard evidence to the contrary save a lot of time, in my experience.

      Testing always delivers results.

    • I know this is an older thread, but since it’s still coming up high in Google it’s important to address for people who come after me.


      This doesn’t need to require much work to monitor seeded emails–work smarter not harder. Time *is* money after all–but cutting corners to save time also cuts income :)

      If you are on your PC, configure one email client such as Thunderbird (free!) to connect to all of the seeded accounts. Mobile phone default mail clients already have this ability. After you send your email checking your inbox and spam folders for each of your seeded accounts is as simple as a few clicks and only takes a minute or two to verify they are there or not. The “Combined View” makes it even simpler to see at a glance which accounts delivered it to your inbox.

      Would you tell your QA folks to not bother sampling the product before it rolls into stores or is marketed online? Or even worse–to only sample specific conditions, which indicates you know it should be checked but don’t want to “waste time” to ensure product quality for every customer?

  2. Do you provide rss feeds for your content? I can’t seem to find any.

  3. @Brad: One way to substitute the seeded email tip is to invest in a professional deliverability tracking tool, such as the one provided by Return Path. It’ll give more insightful feedback at zero effort

  4. Interesting that Point 7 could be an issue. Doesn’t make sense though.. Why should x@domaincom be filtered differently to y@domaincom?

  5. One other important tip:
    Keep your list trim! Remove non-engaging subscribers from your list. The time frame for an engagement is up for debate, of course. Typically, if someone hasn’t opened or clicked in the past 4-6 months, nix ’em.

  6. Good overview, Maciej. Here are two more critical recommendations.

    The majority of email deliverability problems stem from hygiene problems with the underlying list. Marketers that want to optimize their deliverability and performance therefore need to:
    1) Clean and correct problematic and invalid email addresses prior to entering these into your marketing database. This can be done with a real-time email address correction service or through a batch or cloud-based email hygiene and correction service. It’s much cheaper and easier to catch these problems on the front end rather than having to solve blocking and blacklisting issues after they’ve occurred.
    2) Companies should clean their email address files on a regular basis (every three to six months) to help purge the problematic addresses from their files.

    Given that poor email deliverability (and worse yet, blocking and blacklisting) can have a disastrous impact on your bottom line, a little upfront maintenance will go a long way to helping you maximize your email performance and revenues.

  7. Great post!

    I’ve been following the KissMetrics blog for a while now, and you guys always manage to make the most complex issues as easy as string cheese via your presentation of the content.

    I’m still amazed today how many phones calls and/or emails I get looking to sell customer lists. It’s insane. Who still does this?

    One thing that I’d add to this list to improve deliverability of emails is to segment your list of customers – emailing people who have a history of engaging with your past email blasts first. I’ve see this segmentation by initial level of engagement increase deliverability with the likes of GMAIL and Yahoo with the rest of your email list!

  8. Another awesome article from KISSMetrics. I’ve read tons of articles on e-mail marketing, and this is the first one to suggest Return Path. Never heard of it before, thanks for the tip.

    Question about “whitelisting.” Would it be enough to ask your subscribers to add your newsletter’s e-mail address to their Contacts? That seems to be the easiest method. The whitelisting process can be a little complicated and confusing at some e-mail services.

    What’s the best “from” address to use? Should I send from news@domaincom or a personal name, like marcus@domaincom? You mentioned a difference between “support” and “newsletter,” but didn’t say which one was better.

    Keep up the great work.

  9. Mitch Mitchell Sep 16, 2011 at 5:46 pm

    This is interesting stuff. Regarding your #3, I assume you were talking things like autoresponders. One of my friends just ran into a problem with Aweber where, for whatever reason, Time Warner put them on a spam list and pretty much blocked everyone. Had that happen to my business account as well, which I used to send through Time Warner and now go the direct route.

    Sometimes it just doesn’t matter when these large companies pay someone to closely monitor your email if they take it out on everyone.

  10. Maciej Ossowski Sep 18, 2011 at 8:14 am

    Guys, thank you all for your kind comments. I’m glad the post managed to stir a discussion on the inbox placement and email deliverability in general.

    @Erik: Nice tip about re-activation campaigns. I have to admit I recommend the same to GetResponse Customers and the timeframe is usually 6 months for an average mailer.

    @Bill: Ditto. I’ve just DMed you on LinkedIn, by the way.

    @Bret: Couldn’t agree more, especially in regards to Gmail.

    @Mike: Thanks for your feedack. Great catch with the link hosting tip. We’ve all seen Spamhaus blacklisting and similar link shorteners in the past, so senders definitely must choose carefully here.

    @Mitch: What I meant in #3 is teaming up with a reliable ESP such as GetResponse who can put you on a shared platform and manage your reputation.

  11. If I embed a PDF document in the body of the email – is that a problem?

  12. Took me some time to browse through all the comments, but I really like the post. It proved to be very helpful . It’s always neat when you can be informed and entertain. thanks for this nice article

  13. I cannot get my emails to land in clients’ inboxes. Keep falling into spam folder! I use Gmail.

  14. The blog post is very much informative and enjoyable to read. I am considering myself very lucky to get the opportunity to participate in this discussion.

  15. This is a really good read for me. Must agree that you are one of the coolest blogger I ever saw. Thanks for posting this useful information. This was just what I was on looking for. I’ll come back to this blog for sure! I bookmarked this blog a while ago because of the useful content and I am never being disappointed. Keep up the good work.

  16. Some ESPs i’ve worked with actually do the seed list check for you.

  17. Your post is simply spectacular and I can assume you are an expert on this field. Thanks a million and please keep up the fabulous work. Thanks a lot once again.

  18. This is a great posting. It was very informative. I look forward in reading more of your work. Also, I made sure to bookmark your website so I can come back later. I enjoyed every moment of reading it. I am here through Google search engine. I have read this post. Now my knowledge has been increase about above topic. Thanks to blog owner

  19. This is an excellent read for me, Must declare that you are on the list of best blogger I ever observed and I am very thank you to share this.

  20. Your post is simply spectacular and I can assume you are an expert on this field. Thanks a million and please keep up the fabulous work. Thanks a lot once again

  21. Great post, I found it very useful. I’m just curious about the issue of purchasing email lists; is this generally bad practice? I’ve been advised in the past that this is preferable to sending unsolicited emails to people who haven’t subscribed. If that’s the case, what sort of techniques are recommended for building email databases? i.e. How do you go about acquiring new emails and building your database without resorting to sending unsolicited emails and using purchased lists?

  22. hello

    i think the best way to reach inbox is sending email as image only , i know some email will go to spam but not all ….20%spam 80%inbox ….

    i use this way and found it better that html templates

    • Yikes! That is well-meaning but TERRIBLE advice. I own a mailing list company as well as an ESP (enterprise level email deployment service) at and a sender reputation company at On our deployment platform, we send a minimum of 30 million a month for just one of our corporate clients so when I say I know what I am talking about, I do.

      Sending an image instead of HTML is a fast track to the spam folder, blocking (blacklisting), sender reputation damage and other issues. Beyond that, a high percentage of ISPs and webmail hosts turn off images by default which means your recipients will see a blank screen and broken image link only.

      This is the worst of the cardinal sins in email marketing. I don’t mean to beat up on you but I don’t want others to take this advice. You can google the issue and you will find tons of articles that will agree with what I am saying here.

      Using Best Practices such as found in this Blog is your best bet!!

  23. Excellent site, keep up the good work my colleagues would love this. I read a lot of blogs on a daily basis and for the most part, people lack substance but, I just wanted to make a quick comment to say I’m glad I found your blog.

  24. Heather Norwood Oct 07, 2012 at 9:08 am

    It’s very difficult to stay out of the folder even if you’re very careful about what you send. Some of the main email services like yahoo seem to block everything and even when you send messages to their team they still don’t remove blocks. It’s ridiculous but it’s the way it is now. About the best you can do is use some of the filters out there and hope for the best.

  25. Hi,

    passing some link as
    a href=”http://……” to yahoo mail regarded as spam….how to solve this problem ?


  26. Nice tips. Didn’t think about many of these so thanks for enlightening me.

  27. I enjoyed your post. I am guilty of using words prize”, “free”, “bonus”, “buy, “purchase”, “order” etc. I am not sure what you would use instead to get someone’s attention. I thought you need to put something in the subject line. I only emails out to my customers that I have done business with in the past. I am also using an email provider service. I am lucky to get one response after sending out 1000 email blasts.

  28. i want to spam (unpublish) this blog in search engines.

  29. hello everyone.i want to spam (unpublish) this blog in search engines.

  30. Its such as you read my thoughts! You appear to grasp so much about this, like you wrote the e-book in it or something.
    I believe that you simply could do with some % to force the message house a bit, however instead of that, that is magnificent blog. An excellent read. I will certainly be back.

  31. Interesting article.
    When I use the email list I have: Email Addresses with which “From” fields should I delete? “Newsletter”, “noreply”, “news” any other I should search for?

  32. I would like to understand, using a different domain name for email campaigns will increase the open rate, when the emails sent from the current domain are landing up in spam.

    For example:
    for email campaigns:

  33. Shame on you, teaching people to send even more spam


    Trying to stop spam ruining electronic communications

    • I didn’t see anything in this email that promoted spam. Companies need to know the best practices to stay in touch with their customers. Companies need to make money, or they don’t have money to pay their employees, and so on, and so on.

  34. Hi,

    I am using Word Press blog. Whenever user post a comment on an article, Word Press sends an email to the author. By default, all the emails are landing to SPAM folder only. Also, few emails send through Hostgator and those also landing to SPAM folder.

    Can you please tell me what I should do in order to land in SPAM folder.


  35. Hi,
    I work as an assistant to a couple of realtors. We have created our own mailing list consisting of other realtors in our area. It will continue to grow as time goes on so far our list is approx. 300 people. Our mail outs include invitations to upcoming open houses. I’m worries that gmail ( the email we are using to send out all the invites ) will mark most of the emails as spam, or the recipients email address will mark our emails as spam. Any advice on how to avoid that? I have read your article along with several others, but most of them seem to be focused towards big scale marketing, when that is not exactly the case here. Any help is much appriciated!!

  36. Great points which hold up just as well in 2016 as they did when they were written in 2011.

    I would add to this list limiting the size of your batches, and the frequency a particular batch sends to each domain. Since this article was written many of the free services also consider the batch size (how many recipients) and are experimenting with algorithms to check with how many different domain users are receiving email from your address in a specific period of time. In other words, if they block any email with over 50 recipients, then if they receive within 1 minute 50 individual emails with the same subject line from the sender same email address they will treat it the same as if you sent one email with 50 recipients.

    I experienced this while sending out emails to the families and players of the youth baseball team that I coach of all things. Yahoo seems to be the one doing the most work in that area.

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