10.6 - How to REDUCE (not prevent) emails going to spam

10.6 - How to REDUCE (not prevent) emails going to spam

"I can 'prevent' emails going to spam." 😱

That's one of the biggest email marketing myths.

The fact is, there will always be emails going to spam, no matter if you’re sending a one-to-one email personally or using an ESP to send bulk emails. Even the biggest and most reputable ESPs have emails landing in spam, guaranteed.

There are thousands of signals mailbox providers (Gmail, Yahoo, Hotmail, etc.) use to determine if an email message ends up in the spam folder or not.

Here are some best practices to REDUCE emails going to spam:

1/ Maintain a clean healthy list

We’ve covered this in the Let's Break Up / Re-engagement Series.

Consistently delete inactive or cold subscribers who haven’t opened your email in at least 90 days.

Not only will this improve your deliverability and open rates, you’ll also enjoy:

  • Saving money. Email marketing tools charge by the number of subscribers. By keeping only those who want to hear from you, you’ll save money.
  • Easier management as your email list stays organized, tidy, healthy, and up to date.
  • Less spam complaints (and headaches).

2/ Don’t use false sender info

Email authentication is used to verify the identity of the real sender and block harmful or fraudulent email messages (such as phishing and spam).

SPF, DKIM and DMARC are the current standards of email authentication.

Mailbox providers will scan your email headers for these. If your email messages don’t have these, there’s a high chance they’ll land in the spam folder.

Most ESPs will take care of these for you automatically, so you don’t have to worry about it.

However, there are still things you need to pay attention to about your “sending domain”:

  • For example, if I send email messages from this email address: welly [at] birdsend.co → birdsend.co is the “sending domain”, while welly [at] birdend.co is the “from email address”
  • Your sending domain must be able to receive emails and must have a valid MX record. Typically if it’s able to receive emails, an MX record is present.
  • The email address you use as the “from email address” must be able to receive emails.
  • Avoid using “noreply@yourdomain.com” or the likes as your “from email” address”. Some mailbox providers automatically send emails from “noreply” or “donotreply” directly to spam.
  • Your sending domain must not have a bad reputation with mailbox providers in the past. If you moved from another ESP, and your sending domain has been reported for spam too many times, the chance of your emails getting into the inbox is small.

3/ Don’t use a misleading subject line

A/ Pretending to be someone you’re not: “Hey [NAME], I still remember our date two nights ago”

In this example, the sender is pretending to have dated the contact while the intention is actually to sell a dating course.

Using another company’s name in the subject line with the intention to mislead them that you're from that company is also deceptive. For example: “@username, check out the notifications you have on Twitter”

B/ Pretending to be a transactional message when it’s not: “Your Order Confirmation”

Transactional emails tend to have a higher open rate than marketing emails. Usually, it’s directly related to the action taken by the recipients.

C/ Pretending to be a fake conversation thread: “RE: [some words here]” or “FWD: [some words here]”

This tactic was often used by marketers in the past. You may even receive one or two marketing emails using this type of subject line. This trick may have worked in the past, but nowadays, mailbox providers will treat it as spam.

D/ Pretending there’s an urgent issue when there isn’t: “Suspicious activity detected on your PayPal account”

This type of deceptive subject line is as dark as it can be. Not only is the sender pretending to be someone else, but it also contains false information. Mailbox providers think the sender is trying to scam the recipients.

4/ Avoid spam-trigger words, ALL CAPS, and excessive exclamation marks

Some examples:

  • 100% FREE
  • Earn $$
  • Sex
  • Investment
  • Eliminate debt
  • Excessive punctuations or spaces, such as:
    • “F.R.E.E”, “P.ro^fi.ts”, “Get r i c h” → trying to game the spam filters
    • “Where are you???”, “It’s yours!! For free!!!”
  • Hi there! I’m doing great! How are you!?
  • Here’s more spam trigger words from Hubspot

5/ Clean content and minimal design for your email message
  • Don’t use “rainbow” font colors
    • Not only does over the top, multiple font colors trigger spam filters, to your subscribers they look unprofessional and all over the place. It’s like a kid is writing and sending the email.
    • Suggestion is to use a maximum of 2 font colors -- one for text, and the other one for links.
  • Don’t use fancy design
    • As a content creator, do you think subscribers open your emails because of how good looking the emails are…
    • Or because of how the content can be helpful to them?

      Unless you're trying to win design competitions or run an ecom store...

      Sending emails with a good enough / simple design and just let your content take center stage is a better approach than sending fancy-designed emails.

      Here's why:

      ✅ Better email deliverability because simple design means cleaner html

      ✅ Faster to set up and send emails

      ✅ You're giving a personal (rather than a corporate) vibe — people want to connect with other humans, not with brands.

      ✅ The inbox is a place to consume content, not to be in awe of how good looking the emails are.

      If you want to show off your design skills, use a CTA to take people to your website.

      There, feel free to use fancy designs.

      I’ve also asked this in forums, and here’s what folks said:


  • Text to image ratio
    • Don’t use too many images, especially if your word count is low. E.g. You only have 100 words but there are 3 images.
    • This also means never to send out an email with only an image without any text at all.
    • Mailbox providers can’t “see/scan” content inside images like they can scan text, hence it’s natural for them to be wary if an email contains too many images. It could be a phishing or scamming attempt.
  • Image size should be small
    • To avoid long loading times, ensure the file size of the image is small without losing their visual integrity.
  • Include “alt text” for images
    • Some email clients block images by default. Having an “alt text” attribute to your images will make more sense to readers. Eg. if they can’t load your image, at least they can get an idea of what it’s about by looking at the “alt text”.

To get creative, you could use this alt text: “enable images to see me” → which would serve as a “call to action” for them to enable their images. To take this a step further, tease them. E.g. “This is what doing this exercise looks like. Enable images to see me.”

  • Spam filters might also penalize email messages that contain images but don’t have the “alt text” attribute → it may imply you don’t really care about formatting your email properly.
  • Text to link ratio
    • Don’t insert too many links, especially if your word count is low. E.g. You only have 100 words but insert 3 links.
  • Don’t use attachments
    • These could get blocked by the spam filters too. A better way is to link over to the downloadable file.
    • In addition, you decrease the load time of the email.
  • Don’t use video, Flash, or Javascript in your email
    • Most email clients don’t allow / support them. Remember, this is email, not your robust landing page or website.
    • If you want to use video, use a thumbnail image of the actual video (with a play button) and link over to the actual video.

6/ Ask subscribers to add you to their address book

In Gmail, it’s very easy. Open the email message → hover over the sender name / email address → more info → click [add contact icon]:


For other mailbox providers, I’d imagine it to be pretty straightforward too. Educate your subscribers to add you to their address book.

7/ Include a clear unsubscribe link and physical mailing address

To comply with the CAN-SPAM act, include a clear unsubscribe link and your physical mailing address in your email footer.

This also brings an additional benefit -- you allow subscribers who’re no longer interested in you to take themselves off your list. This is a very welcome move. Why keep sending emails to folks who no longer want to hear from you? If you keep sending them emails, not only will they despise you, they’ll mark your emails as spam → you’ll get lower deliverability and may even be banned from your ESP.

8/ Reduce the possibility of people marking your emails as spam

Here are a few ways you can do that:

  • Use double opt-in
    • This way only folks who genuinely want to hear from you are on your list
  • Give subscribers the right expectations
    • Only send relevant emails (topics the subscribers signed up for)
    • Frequency -- if you’re going to email them daily, be upfront about it
  • Send broadcast / newsletter emails on a predictable schedule (e.g. weekly / bi-weekly / monthly)
    • If you haven’t emailed them for a while (say 90 days), they’ll probably forget about you.
    • By sticking on a predictable schedule, you eliminate surprises.

9/ Good email marketing tool / ESP for good deliverability

You’ve worked so hard to build your email list. Next, you want to minimize the leaks in your email marketing efforts (so that your emails reach the maximum number of people possible) by using a great ESP that provides great customer support, while still not costing you an arm and a leg.

A great ESP will take care of all the technical authentication and verification for you -- like SPF, DKIM, and DMARC. It will also maintain and constantly improve its sending reputation so that your emails have the highest chance of landing in subscribers’ inbox.

Feel free to do your due diligence for options. Obviously I’m biased as me and my team run BirdSend — where we relentlessly work on it every day. We batch release updates to BirdSend every week or 2 weeks, depending on the complexities of the updates.

BirdSend is built by indie creators for indie creators. If you’re not a creator, we’re not for you.

If you’re a creator with a huge funding or team behind you, we’re also not for you. Hence why we call it “indie”. We’re more for solopreneurs or those with a small team member of less than 10.

Creator means someone whose business involves creating content the majority of the time.

BirdSend is not as famous as other ESPs yet, hence the affordable pricing. Our pricing does not reflect the quality of our tool. But don’t take my word for it. See what actual customers and users say about us.