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Grow | Email Deliverability 101
Grow | Email Deliverability 101

Email deliverability is the measurement of emails that go to your Subscribers’ inboxes vs. spam/junk folders.

Updated over a week ago

Mailgun best practices on email deliverability

Email deliverability is the measurement of emails that go to your Subscribers’ inboxes vs. spam/junk folders. You want to ensure your emails end up in your Subscribers’ inboxes, so high deliverability should be a critical focus.

You have the power to promote high deliverability by being Subscriber-focused. Send content consistently, and send content that they will actually want to engage with. Give them the power to choose how often they hear from you, providing opportunities for authentic engagement. All of these positive drivers will help you end up in more inboxes, and avoid spam folders.

How is deliverability measured? Many factors influence email deliverability. Generally, three questions are asked by mailbox providers (such as Yahoo, Google, Outlook, etc.) to determine what inbox an email ends up in.

  • Is this message safe?

  • Is it wanted by most Subscribers?

  • Is the message wanted by this specific person?

If YES is the answer to all 3 questions, the email will most likely end up in the inbox. Otherwise, it will end up in spam.

What is your sender reputation? Mailbox providers rely on your sender reputation to create a ‘sender score’ using algorithms. There is not a one-size-fits-all approach to this, so each provider keeps their specific calculation and algorithms private, but one critical factor is how subscribers engage (or fail to engage) with your messages. How your subscribers interact with your mail is known as subscriber engagement. Their engagement with you can be positively or negatively impacted by subscriber behaviors. Here are a few tips for promoting positive subscriber engagement:

Subscriber List Health

  • Focus on quality vs. quantity. Use subscribers who have given you explicit permission to communicate with them.

  • Use a double opt-in or ReCaptcha for form security to prevent bot usage.

  • Clean, or scrub, your list frequently of cold subscribers. Having a growing list of unengaged subscribers will drop your reputation as those emails start filtering to subscribers’ spam folders.


  • Try to not make sudden, drastic changes to the way you send messages, as mailbox providers will view these messages as risky, likely filtering them to spam.

  • Using multiple domains is okay, but be sure they are recognizable and have been active within the last 6 months.

  • Volume: send communications to a consistent number of subscribers.

    • NOTE: it is normal for your list to grow or shrink, but try to not have any major swings (don’t jump from 2,000 subscribers one day to 10,000 overnight).

    • If you have a large influx of subscribers, divide them into batches to slowly grow your database.

  • Frequency: Maintain your reputation by ending at least one email per month. If you go ‘dark’ for too long, your reputation won’t be maintained and you’ll essentially be starting from scratch with your next email. Contrarily, don’t send emails too frequently as it could be flagged as spam.

    • NOTE: it is highly recommended to give your subscribers the option to determine how often they want to hear from you.


  • Content influences your deliverability as an underlying data point, especially if you don’t have good consistency. If you send inconsistently, the actual content can be used to determine the safety and subscribers’ desire for your content. If you do send consistently, then content is often ignored.

  • Don’t use spammy words/phrases, or gimmicks. Try to make your email sound more conversational and human even if you’re selling something. Don’t make it sound to urgent or overly promotional. Don’t use “tricky” subject likes like “RE: Your Order #12345”

  • Eliminate link shorteners: these are often used by spammers and some spam filters may automatically red-flag these. Use the direct, full links for transparency.

  • Focus on your image-to-text ratio. While there isn’t a magic recipe here, the best practice is to have enough text so if an image fails to load, the text will still effectively communicate your message.

  • Drive authentic engagement: encourage subscribers to engage authentically. Maybe ask them to reply to your message with their favorite show they’re currently binge watching, their favorite song, or a great recipe they’ve recently cooked.

While it may seem that only your Grow emails are being impacted and this is an issue with PushPress, it is more than likely because of the content, your email sender to domain relationship, or some other variables. Currently, your Grow emails come across as more marketing based (business to person) while the emails you send from your actual Gmail account are coming from a different IP (one from Gmail) and come across more transactional (person to person). Also, the sending volume is not the issue. However, because you are sending at the volume you are with low engagement, that would be an issue.

What I wanted to do was personally connect with you to let you know that our team did look into your account and can assure you that from a technical standpoint everything (TXT records - including SPF and DKIM) is set-up correctly.

Since we know your domain is set-up correctly, the next step is to look at the other issues that influence deliverability. Let me start by reviewing some best practices for email. The items in blue are things you can currently improve.

● Send only to recipients who explicitly subscribed to your emails (not list purchases, list rentals, or email appends).

Offer an unsubscribe link, so that the recipient can unsubscribe immediately. Issue: There is no method to unsubscribe at the bottom of your emails.

● Use consistent sending IP addresses and domains for your bulk email, but do segment marketing and transactional email streams.

Use a consistent From: name and address to clearly identify your brand.

Issue: You are using multiple sending names such as GYM NAME, OWNER FIRST NAME, and OWNER FULL NAME. Because you are not consistent with who is sending the emails from your Grow IP, you are losing reputation points with email providers.

● Make use of Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) to authenticate your emails.

● Periodically remove inactive subscribers from your list.

Issue: Periodically removing contact who aren’t engaging can help your email

health tremendously. This is called scrubbing your lists and a best practice for maintaining a healthy email list and engagement score.

● Don't reactivate email addresses that are already on your unsubscribe or suppression list.

Now that we’ve covered a few of those bullet points, let’s discuss the other key elements that influence your deliverability.

Your reputation.

Overtime, your domain and IP develop a relationship with an ESP (such as Gmail, Hotmail, etc.) This is known as your sending reputation. One of the most important assets you have in the email world (much like the real world) is your reputation. If you do not have a good reputation tied to your domain and your IP address, your email will not reach your recipients’ inboxes. Due to its popularity and its unique ability to push information to users, email has been overrun with spammers (as if you didn’t notice). Depending on your definition, approximately 90% of all email is spam (source: MAAWG). Due to this, email service providers (“ESPs”) like Gmail, AOL, Yahoo and MSN/Hotmail have declared an all-out war on spammers. This has made our inboxes a more pleasant place. This also makes it very important to manage your email reputation. If it is not impeccable, you will get caught in the ESPs’ spam filters.

A good analogy for your email reputation is your personal credit score. Obviously, a bad reputation will hurt you. However, not having a reputation will also hurt you. If ESPs don’t know you (or more specifically your IP and domain) they will assume the

worst and filter you, at least initially. It’s tough to blame them given all the spam out there. Due to the importance of reputation, a significant portion of our discussion on best practices revolves around building and maintaining your email reputation.

Your reputation is tied to your domain name.

Your email reputation is not only tied to your IP, but your domain name as well. You should keep this in mind as you set up your email infrastructure. For the same reasons as above, It is a good idea to have separate domains or subdomains for your marketing, transactional and corporate mail. We suggest that you use your top level domain for your corporate mail and use different domains or subdomains for your marketing and transactional mail.

While it is not required to use the same domain in the From field of the message as the actual domain sending the message, it is highly recommended. Hotmail is especially finicky about this requirement and has a higher propensity to filter your messages to junk if the two domains do not match.

You should also make sure that you are using a well regarded DNS provider and that you publish all of your contact information in the WHOIS record. If you are hiding your contact information through a proxy, ESPs may take that as a signal that you are spamming.

You should allow a clear method for a contact to unsubscribe.

It is important to give your recipients the ability to unsubscribe from emails. First, it is required by the CAN-Spam Act. Second, if you don’t give them this option, they are more likely to click on the spam complaint button, which will cause more harm than allowing them to unsubscribe. Finally, many ESPs look for unsubscribe links and are more likely to filter your email if they don’t have them.

Unsubscribe links should be featured prominently. Spammers frequently use hard to see or fraudulent unsubscribe links. If your links are not prominently displayed and functional, this will decrease the credibility of your business and may get your email filtered. Monitor your unsubscribe link activity and remove those who wish to opt out of your mailing list. If you are responsive to such requests, it is more likely that recipients will click the unsubscribe button rather than report your mail as spam.

Your recipient’s engagement rate is important.

In addition to processing bounces, complaints and unsubscribes, ESPs measure your reputation through the engagement of your recipients. If recipients are opening, forwarding and replying to your emails, it will improve your reputation. This is what makes ‘do-not-reply’ emails so offensive. At many ESPs, it is also helpful if recipients add your email address to their address books.

You want to encourage your contacts to open, reply and add you to their address book. The more contacts you have NOT doing this the lower your engagement rate will be. This is while only sending to quality contact is important. Overtime, you can remove contacts who are not engaging to help keep your engagement percentage as high as possible.

Your email’s content is critical.

There are a few tricks to remember about content besides the mantra of ‘sending something people want’. Personalize your emails to each recipient. Ideally, the content should reflect the recipient's specific interests or usage patterns in your application. At least address them by their name…

● The higher the text to link and text to image ratios, the better. Too many links and images trigger spam flags at ESPs.

● Misspellings, spammy words (buy now!, Free!) are big spam flags, as are ALL CAPS AND EXCLAMATION MARKS!!!!!!!!!!!!!

● The domains in the from field, return-path and message-id should match the domain you are sending from.

● Make sure you are using unsubscribe links and headers in your emails. Many ESPs (particularly Hotmail) pay attention to this and if they are not there, you are likely to get filtered.

● Links should include the domain that is sending the email. Also, popular url shorteners can be a bad idea because they are frequently used by spammers. ● A/B test your emails to optimize recipient engagement. Subject lines are particularly important.

● Typical elements of poor composition such as misspelled words, excessive use of caps and large fonts, odd spacing, repetitive use of exclamation marks

and promotional leads such as “free” and “buy now” are precisely the type of things that will get your mail sent straight to the junk folder and risk getting your domain blocklisted.

● Sending HTML email is not well received by ESPs. If you’re sending an HTML email, it’s important to include a text-only version of the content for recipients without modern email clients. This is important not only from a common sense standpoint, but it has a lot to do with whether your email gets to the recipient or is diverted as spam.

● Furthermore, spammers tend to have a high ratio of HTML to text as they often favor images and frequently embed their text in an image. Spam filters are designed to filter email that contains

● Although it may be tempting to load your email with links to all kinds of great info, don’t. A high link to text ratio is a major indicator of spam. Also, watch out for those URL shorteners, they will likely get your message flagged. Remember your email will be completely ineffective in customers’ junk mail folders.

.fit vs. .com

If your domain ends in “.fit” instead of “.com” email providers are not as likely to view your domain as a trusted source. While this isn’t something you can change now, it is important to know that you are already starting with a few less reputation’s points due to your domain ending in “.fit”.

In Review, here are the suggestions to get you started towards better deliverability:

1) Send only from from Grow and use a consistent sending name (pick either Gym name, Owner Full name, Owner first name, etc. and keep it consistent for ALL emails). All of these emails are different in how they setup the from name and email. You want the ESP to know what email is going to come from who.

Note that at the bottom of your template you have this listed:

2) Use a functioning method to unsubscribe.

3) Instead of using the email template builder and inserting buttons, images, videos, etc. Keep is more simple and use the email builder in the workflow itself. Keep in mind the items we discussed above when creating content, as I see may spam triggers in your emails.

Creating your emails in the workflow itself without the use of a marketing-type template is recommended. When saying “in the workflow itself” I am referring to the “Message” area on the right-side of the image below with the red square around it.

Again, thank you for choosing Grow. You are a valuable customer.

Unfortunately, email deliverability is complex and that is why education in your sending habits is important.

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