6 tips to never fall into the spam folder again

Learn how to improve the deliverability rate of your transactional email with six tips to never fall into the spam folder again!

Imagine the following scenario: you decide to create an amazing transactional email which is sent to contacts as soon as they make a purchase in your e-commerce. The subject line is personalized with their names, the content was created especially to your persona and it also has an exclusive discount for their next purchase. It’s the perfect transactional email to retain customers!

The problem is, in the middle of the way, your wonderful email message ends up being identified as spam and your entire retention strategy goes down the drain. To avoid your next messages from going through this same path, you'll have to take some very important measures to avoid your transactional email from being identified as spam.

Quick question: what is SPAM?

Besides from being a famous american brand of canned meat, the spam is an email message unsolicited or unwanted by its recipient. While the most spam messages come from unknown senders with extremely questionable content, sometimes the ISPs - Internet service providers - or even the own recipients categorize legit email messages, sent by serious companies, as spam. Between February 2015 and May 2016, spam senders stole more than 104 million dolars/month from american companies through wire transfers fraud.

If your contacts click on the "This is Spam" button when reading your transactional email, the ISP will be aware that it’s an unsolicited email, and that particular email gets defined as spam. Each ISP has different rules and limits for the number of acceptable complaints and spam reports for a domain: if you exceed the limit, you can get blocked and all your future emails, as wonderful and attractive they can be, won’t escape the contact’s spam folder.

Off-topic article: The Origin of SPAM (The Food) & Spam (The Email)

Keep your transactional emails away from the spam folder

Due to a series of malicious practices from different companies and senders from around the world, the ISPs and recipients are keeping their eyes open to define what is spam and what isn’t. So you can show that you have a serious business and wanna provide a better experience to your contacts, we’ll give you some tips to keep your transactional emails away from the contact’s spam folder.

Looking for a specific tip? Use the shortcuts below:

Optimize the email’s content

First of all, you have to optimize your transactional email’s content if you don’t want it to be caught in a spam filter. When you send an email, the ISP analyzes its contents to determine if it’s an unwanted message. After all, as you don’t like to get all those annoying emails full of suspicious links, the providers must ensure their own users don’t get the same kind of content.

Is like the ISPs goes all over your email’s content with a fine-tooth comb, from the sender's email address to the footer’s signature, searching for anything that could be spam or harmful to the recipient. Check out some tips to write your transactional email and go right through the spam filters:

  • Sender’s email address: the first item is the username and domain from where the message is coming from. Avoid: using public domains such as Gmail, Hotmail and Yahoo; "coded" names, full of numbers or random characters, like "out3.pod5.sac1.efsys.net" or "server_email05132016". Wanna make your contact comfortable with your transactional email? Use your own name and domain: it can also increase the engagement rate with your email!
  • Subject line: is what will make the contact click to read transactional email’s content. On the other hand, the ISPs also pay attention to the subject line: if you like using the words "free", "discount", "off", "free money", "$$$" or even UPPERCASE words, you better change your strategy or you’re get an special place in your contact’s junk mail.
  • Email attachments: maybe one of the most dangerous itens in a malicious email message. If you really need to send some kind of file to your contacts - like a receipt or an invoice - you better upload it in a server (preferably in your own domain) and offer a link so the contact can download it. In the past years, emails with dangerous .zip file attachments, .html files and .exe applications made a grand return in the spam world: be careful!
  • Email images: no more trying to save time by sending just one massive image with all the email’s content to your contacts. ISPs may see an email with too many images as spam, even if they’re attached or inserted with HTML. Be careful to keep a balance between text and images: your emails will be prettier than ever and your contacts will receive it just the way you send them.
  • HTML content: make sure that the HTML of your email is coded correctly, because broken images and even unusual HTML tags are used by spammers to hide harmful links. Opt for a clean design and be careful on the way your email’s HTML is build.
  • Unsubscribe link: indispensable for all transactional and marketing campaign emails. The "Cancel subscription" must be visible and easily accessible for the contacts who doesn’t want to receive your emails again. Don’t worry: if your transactional emails are engaging and well produced, there’s no problem on adding the "Cancel subscription" link right on the top of your email.

Test your email with a spam checker

After optimizing the content of your transactional emails, a good practice is to verify if the emails you intend to send have chances of being considered spam by the Internet service providers.

You can use SpamAssassin, which filters the messages that you send through your server and qualify which of them may be blocked by ISPs through a "spam score".

Both the content and the SPF and DKIM configuration - don’t worry, we’ll get there - are analyzed by it. With that, it’s possible to know what are the chances of your transactional email be considered spam right before sending it through your server.

A alternative for SpamAssassin is Mail Tester, a free service that requires no installation. You just have to send a copy of the transactional email to the email address informed, then check your score.

Mail Tester

Besides from filtering your message through SpamAssassin, Mail Tester also evaluates the HTML content, checks if there are broken links, alternate text attributes for images, if your domain is blacklisted and if your domain’s SPF and DKIM are configured correctly.

There you go! The content of your transactional email is ready, but it’s still too soon to send it. It’s time to proceed to our next step to avoid sending it directly to your contact’s spam folder.

Avoid the spam traps and honey pots!

Spam traps are resources created by ISPs to catch spammers all over the Internet.

The ISP's tactic is simple: they own different old, inactive email addresses disguised as regular emails to verify which domains and senders are sending messages to these addresses.

The Composite Blocking List keeps an updated database with the number of spam messages sent to spam traps, and the numbers are shocking: an average of 1.300 spam messages are sent every second!

Composite Blocking List

There are two kinds of spam traps:

  • Honey pots: email addresses created by ISPs and scattered through the Internet, in forums and websites. This practice allows the ISP to find spammers who access these kinds of pages just to "steal" email addresses and send malicious content without the contact’s permission.
  • Recycled email addresses: when an user decides to abandon or cancel an email address, some ISPs reactivate these addresses and start monitoring the messages sent to them. With that, ISPs can discover companies that don't keep their contact lists clean and updated, or companies that bought contact lists.

To run away from spam traps, just keep your contact list clean, avoid sending emails to old addresses or which didn’t have any interactions - opens and clicks - for the last three months. The most important thing is to be sure that your contacts authorized the sending of emails to their addresses through opt-in.

Learn more: What do "opt in", "soft opt-in", "double opt-in" mean for email campaigns?

Beware the blacklists

If the domain you use to send your transactional emails ends up in a blacklist, you’re gonna have a bad time making the ISP trust the content of your email messages, no matter how harmless and well-structured they are.

The blacklists are lists of DNS domains that were reported as spammers by users when they click the horrifying "This is Spam" button, or were caught by an ISP spam trap. The blacklists are used by servers and providers to check which domains have a history of sending spam, then decide if its email messages will be sent or blocked.

You can check if your domain is blacklisted using the Blacklist Check tool, which automatically verifies if your domain or IP is present in over 100 blacklists all around the world.

Blacklist Check

If you found that your domain is in one of the blacklists, don’t panic: the most reasonable thing to do is contact the site that added you to the blacklist in the first place, and ask how to proceed with the removal of your domain from the list.

Some blacklists remove the domains from their lists after the domain solve the problems which led it to be blacklisted, such as SPF and DKIM configuration. Other blacklists remove the domains automatically, but only after a very long time.

Define your domain’s SPF and DKIM

To make sure for ISPs that you transactional email is safe and it’s coming from a valid and secure domain, a good practice is to authenticate it using the SPF and DKIM configuration. It’s not an easy task keeping spammers away from the user’s inbox, and the SPF and DKIM help the ISPs to correctly identify legit senders. This way you’ll have more guarantee that your email messages will be successfully sent to your audience.

SPF stands for Sender Policy Framework, a method that specifies which email servers and platforms are allowed to send email messages through your domain. The SPF communicate with the ISP and confirms that a specific platform or server has been authorized to send your transactional emails.

The DKIM (Domain Keys Identified Mail) is an authentication system present in both the email message and the DNS server which sent the email. With the DKIM configured, the transactional email recipient will be sure that your domain is real and reliable.

Read more: Do you know what SPF (Sender ID) and DKIM (Domain Key) mean?

Sometimes transactional email platforms have a specific step to configure the SPF and DKIM of your domain. Check out this tutorial we’ve prepared to you configure your domain’s DNS and authorize Maildocker to send your transactional emails.

Configure the Return-Path

The Return-Path isn’t obligatory, but it can help to avoid your transactional emails from going to the spam folder. It’s a hidden field where the email sender defines to which address the bounces - emails returned from the recipient’s inbox - will be sent. Usually is a special address in the same domain as the address that’ll send the email, e.g. "[email protected]".

That’s why defining the Return-Path is so important: when we send an email and choose a custom sender address, the ISPs may think the email address is a fake. The Return-Path must be used with the SPF because both will authenticate your email address.

Be careful not to mistake Return-Path with the sender’s address. If you use a transactional email platform you may choose a custom sender’s address, but if the message cannot be delivered for some temporary error (soft bounce), the email will be sent to your Return-Path address.

There you go! If you made till here, you can already send your transactional emails because there are more chances that it’ll be correctly delivered and go right through the spam filter.

Remember: if you want to ensure the best deliverability rate to your emails, all these tips must be followed at all times. Each one of them adds a new level of protection to your emails, and the result is that you’ll always have a guaranteed spot in your contact’s inbox!