How To Land Your Emails In Inbox? The Ultimate Guide!

How To Land Your Emails In Inbox?

If your recipients never see your emails in their inboxes, then the effort and time you consumed to create and run your email marketing campaigns were simply wasted.

HubSpot gives the following definition of email deliverability:

The measurement and understanding of how successful a sender is at getting their marketing message into people’s inboxes.

Fortunately, you are here! in this Guide, I will Explain and Show You everything you have to know to make sure your emails land in the inbox and not spam.

Spam Filters 101

When you send an email to someone, let’s say to a Gmail account, what’s happening in the background is that you are contacting or communicating with the Gmail Mail System. and Gmail like any Email Service Provider has what we call “SPAM Filters” which are a layer of security to protect their users from fraud & spam messages. check the diagram below:

SO as you can see, whenever you send a message to a target mailbox, the mail server will filter the message using the spam filters and determines whether it’s a spam message or not.

How Spam Filters Work?

To send your emails directly to the inbox, simply you need to pass spam filters! And to pass spam filters, we need to understand how it works.

Years Ago, The Spam Filters was configured to follow certain rules in order to filters emails. Like Image ration in your emails, blacklisted domains, spam keywords, Sender Reputation, Volume…

I’m not saying that those are not factors anymore, NO. But the technology changed, the way the spam filters work changed.

Today Spam Filters are Intelligent. it can learn with the new machine learning technology!

So Spam Filters are able to analyze Billions of emails and learn from user activity and patterns on how to filter spam emails!

Why this matter?

Maybe you are wondering… Ok what changed now, what should I know?

Let’s see some examples:

Before, in the old days! if you send a low volume of emails, you will be ok and your emails will pass the filters.

But Today, these smart filters will detect spam even if you send 10 Emails per day!

Even if you send an inconsistent number of emails like suddenly you send 100 Emails a day whereas you were sending like 10–20 emails daily. this is also may flag you as spam. and here why it’s important to be consistent when sending emails. (we will talk about this later in more details).

Another example is your domain, today, if you get a new domain, it may be blacklisted automatically for 30 days as a precaution. and using an old domain is better for your reputation.

So yes, it matters! and you need to learn the rules of the new game!

Let’s Inbox!

Ok Friends, Now let’s dive in and cover almost everything you need to know in order to avoid spam and land your emails in the inbox.

1. Subject Line & Message Body

Subject Line

When you send an email, the main two parts that form your message are the Subject line and the Message Body. So Simply you need to ensure that both will not trigger the spam filter. How?

Just Make sure to avoid any bad or spammy keywords in your Subject Line and in your message content. to do so you can simply do the following:

When you write the subject line, test it using subject line testers and ensure its a good subject line. So use a service like SendCheckit Subject Line Tester which is a free online tool and make sure you get a good score.

Example of a Bad Subject Line: “GET FREE [100$] GIFT — CLICK HERE!”

This Subject Line is bad Simply because it contains some Bad & Spammy keywords like “Get”, “Free”, “here”

Also, it contains bad characters like the exclamation mark “!” and the All caps letters.

Example of a Good Subject Line: “Email Marketer? Want to Boost Conversions

Simple, Clean, and Perfect Subject Line to use.

If you are following my Email Marketing Mastery Free course, maybe you have passed by my lecture about “Writing the perfect subject line“, if not, you can watch here:

Message body

Like Subject Lines, The Message Body also must not contain any spammy or bad keywords like the following:

Earn $, Get Rich, 100% Free, FREE ….and other keywords.

You can check a list if Spammy keywords at Hubspot here.

Other than spammy keywords, there are some good practices to follow when you write your email:

  1. Text to image ratio: Spam filters are suspicious of emails made up of mostly images.
  2. Thoughtfully add links. You don’t want to add links more than 3 times in one email. (we will talk about links more later)
  3. Personalization. insert personalization into your emails (person name or company).

Note About Personalization: Although it’s a good practice to personalize your emails after I did a lot of tests and check-up different sources, It didn’t seem to be big deal maybe except in Cold Email Marketing.

If you Go Neil Patel’s website, Backlinko, or H-educate, you will see that to subscribe to the newsletter, you will need to enter only your email address. so emails are not personalized and email campaigns are performing greatly and delivery rates are up to 90%.

Optimized Your Subject Line and Message Body? Great!

2. Your Sending Domain

The Second important thing that you have to look into, is your Domain name. the domain that you are using to send emails.

example: I use in my campaigns, so “” is my sending domain.

Before you send your email campaigns, you need to make sure your domain is clean and not blacklisted. How to check?

Simply, you can go to and use the blacklist tool which can show you in seconds the status of your domain, here is mine:

Note: if your domain is still new, it may be blacklisted automatically by SEM FRESH, It’s normal, it will be removed automatically after 15–30 days.

Checked Your Domain? Great!

Another Important Note to Know!

If you are sending cold emails if you are a cold email marketer, it’s better to use a domain other than your primary business domain. because if it got blacklisted, your main domain will stay safe.

So Just Go and Get a domain dedicated to cold email marketing only.

For example, my mail domain is when I do some research and tests about cold emails, or when I send some cold campaigns, I use another domain, which is

Gmail Postmaster Tools

The Next Step is to add your Domain to Gmail Postmaster Tools to Monitor its reputation, Spam rate, Authentication, and other stuff which will help you understand your email sending level and detect any problems.

Here is an example for one of my domains:

Added Your Domain? Great!

Let’s Move on.

3. URLs & Links

Spam Filters are very sensitive to the links that you add to your emails. Because it’s where the user will take action.

So you need to take care very well when adding your links.

The First thing you have to check, is if the Domain URLs are blacklisted or not. and if it’s safe or not.

Ok, about the blacklist, I mentioned that you can use Mxtoolbox to check.

What about safe links?

Simply you can use tools like Google Safe Browsing, Kaspersky VirusDesk, or Phishtank to test any URL.

So always check your links before adding it. This is one.

The second thing you have to take care of is the Affiliate & CPA Offer Links. Don’t Ever Ever add Affiliate links directly into your emails!

How to add Affiliate Links to our emails?

I said “Don’t ever add to emails“, then how we are going to promote affiliate using email marketing?

if you work as an Affiliate & CPA marketing Like promoting ClickBank Offers, Amazon products, Maxbounty Offers, or whatever. Then one of the main channels is to promote using email marketing.

Of course, I am not talking about spamming here! You have a subscriber base, you know their interests, you can send them some special deals and promotions.

as an example, I am subscribed to 3 Affiliate networks. One is related to web hosting, one is about email marketing tools, and the third is the Udemy affiliate program.

There is nothing wrong to send my subscribers a notification that Udemy is running a sale if you would like to get a course, and I attach my Udemy affiliate link. this 100% legal, and this is how it works.

Anyway, let’s go back to our topic, How to promote affiliate offers through email marketing?

Here we have 2 Approaches and I do prefer the second one because of its more professional.

What are these two approaches?

  1. Cloak Your URLs.
  2. Use a Landing Page.

Cloak Your URLs. (Masking Links)

URL Cloaking, or what we call Stealth Forwarding is a technique used to hide the target URL that you want to use to visit and mask it by another one that looks like a normal URL.

How this works?

We use an HTML frame on our web page to hide the main URL. or we can use HTML redirection.

If you are not familiar with such terms, it’s ok, anyway, It’s so simple. You can watch the following video to learn more in detail how cloaking works and how to create your own Cloaker.

In General, we have two methods, the method explained in the video, or you can simply use a URL cloaking service.

You have to know that not all links are allowed to be used in frames, so you will be obliged to use redirection.

Use a Landing Page.

The second option which I do prefer is to use a landing page or a normal post on your blog that is talking about the offer, then you can add your links inside the post.

So in your emails, you will be linking to your website landing page or blog post, and everything will look normal.

Now your URLs are safe. Great!

4. Email Tracking

When you send an email marketing campaign using any email marketing service or with your system, you will have the ability to monitor and track your emails.

So we can know who opened the emails, and who clicked the emails, from which countries and so on.

Why Tracking may trigger spam filters?

To know why you need to know how attacking works in the background. how email marketing application know if someone opened the email or clicked on a link?

Simply, when you enable tracking, what happens is that automatically a small hidden image will be added to your email. this hidden image will have the source attribute as a Link which is responsible for connecting to an online service and sending information about the email.

So when someone opens an email, this hidden image will load automatically and the link will be executed informing the server that this email is opened.

And what about tracking Clicked links?

Now to track clicks, what will happen is that all the links in the email will be replaced by other URLs by the email service or application. so, in reality, we track special URLs and not the real URLs.

so when these special Links are clicked it can be recorded by the email service then it redirects the user to the target URL.

here I am announcing my email marketing mastery free course, and I added a link to YouTube (the Link in blue) which is the real link.

But my email marketing system, replaced it automatically by the tracking URL (in red). so now the user will click on the link, the red URL will open records the click and redirect the user to the blue link.

I think it’s simple.

So after we understood how tracking works, I think you know why it may trigger spam filters? yes?

Simply, you need also to ensure that the tracking URLs are safe and not blacklisted.

Also as a good practice, if you are using an SMTP service like Sendgrid or Sparkpost, or any other SMTP service, or maybe if you are using your own SMTP server. configure always a custom domain for tracking other than your main domain.

Done with tracking? Great!

Full-time writer & I write on Digital Marketing & Online Bussiness Education.

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