Improve Email Deliverability – A Guide to Best Practices

Improve Email Deliverability – A Guide to Best Practices

With crowded consumer and business inboxes, email deliverability and inbox placement has become a top priority for marketers in recent years. Getting emails flagged as spam or blocked by mailbox provider has an impact on sender reputation and future inbox placement.

Many marketers use “deliverability” as an equivalent to “inbox placement,” but the terms are not the same. Emails that go into Spam folder are considered delivered, where is marketer’s goal is to ultimately get emails into subscriber’s inbox.

The major factors that affect deliverability are:

  1. Global engagement (overtime, across campaigns)
  2. Content and format of the email (spam words in subject or message body, format – use of images, etc)
  3. Relative engagement for you (sender) versus other senders in the recipients inbox
  4. IP reputation
  5. Sender reputation (e.g. sender being your domain or exact email address the emails are sent from)
  6. Server and domain configuration (DKIM, SPF, etc)

email deliverability factors

Email deliverability factors

On the diagram above, the green box represents factors that vary and change more with each campaign sent and the square on the left with 4 factors are not subject to dramatic changes on a per campaign basis. In this guide, we are covering 5 out of 6 factors, but you can learn more about IP reputation management here.

The list of best practices below can help you achieve better email deliverability from building and maintaining a strong sender reputation, while improving your engagement. 

Global engagement – keep bounce rate low

An average email list decays at a rate of 2% per month for B2C lists and 3% for B2B lists. The rate is higher for B2B lists because people change work emails more frequently than personal emails, due to job changes. So if you haven’t engaged with your email list for more than 6 months you are likely to have a more than a 10% bounce rate on your first bulk campaign. A bounce rate over 10% can get your account suspended with many email service providers (ESPs), but it also has a negative impact on your email deliverability and sender reputation, not to mention cost (since you pay to send email to invalid addresses). Inbox providers pay close attention to bounce rate and may block emails from a sender that attempts to deliver to invalid email addresses.

At BigMailer, a bulk campaign with a bounce rate over 8% (default, configurable by customer) is automatically paused to protect sender reputation.

Old and unengaged lists should be validated before being imported into an email marketing platform. Most email validation providers recommend that you validate your entire list once a month, or before every campaign you send, to keep your bounce rate as low as possible. While that tactic can be pricey, the good news is that most email validation providers offer great volume discounts for purchasing credits in bulk (that usually never expire).

We have partnered with low-cost email validation services Bouncer (GDPR compliant, recommended for customers in Europe) and TheChecker to get our customers a discount on their services.

Email content and format (including email headers and links)

1. Use a custom tracking URL in your emails

Using a custom tracking URL in your emails can help your emails appear more authentic and help with inbox placement. Consider customizing tracking URL for your emails, using the same domain as your sender address. For example, if your sender is sales@your-domain.com you can use email.your-domain.com as your tracking URL.

custom tracking URL

Examples of commonly used tracking sub-domains

This will require updating your domain’s DNS records (to create that email subdomain and map to email provider servers) and then adding the updated records to your email provider’s platform as a configuration or setting. Most market leaders allow this, although some call it white labeling and most charge extra for it or make it available on higher tier plans. 

2. Create a plain-text version of your email

While only a tiny fraction of your audience may see the value in a plain-text email, SpamAssasin, a widely used spam tool, considers it essential. The tool assigns two points to your email if no plain-text version is available. If your message reaches a score of seven, it’s identified as spam, so two points is a pretty big penalty for something that’s fairly easy for a savvy marketer to execute.

While some email platforms (like BigMailer) will auto-generate a plain-text version from the HTML version, most of them don’t require one. If you have to create a plain-text version yourself, don’t cut corners – it should match the message in the HTML version and not be any shorter. Check out this article from Litmus for more guidance on formatting plain-text emails.

3. Make it easy to unsubscribe

Making it super easy for users to unsubscribe is not a tactic that’s obvious to benefit the sender, but it is. If email recipients can’t easily locate the unsubscribe link they are likely to hit the Spam/Complaint button instead. Complaint is the worst type of engagement for your email campaigns. 

Your unsubscribe or “subscription preferences” link needs to allow a user to either opt-out from your brand communications or  select the message types they want to receive (see the example below) and not to a page that requires them to log in to their account to retrieve or save their preferences. The latter has become a more prevalent practice among some high profile brands that use their own built-in-house email tools. This practice is actually in conflict with anti-spam laws. It’s advisable to provide users with a straightforward method for getting off an email list and honor that request in a timely manner.

It may be helpful to offer subscribers a way to opt out from certain communications instead of all brand communications at once. Providing this option has become even more necessary with the introduction of General Data Protection Regulation (GDPR) laws in May 2018, which states that the consent to receive emails should be explicit and not be bundled (e.g., if subscribers only opted in to receiving product updates, you can’t additionally send them promotional emails or messages on behalf of your partners).

Example: unsubscribe page with preferences format

Example: BigMailer.io unsubscribe page with preferences format

4. Specify a useful sender (from) address

Be it a question or general feedback, email recipients commonly want to respond to the messages they receive. For this reason, it’s best if your reply-to email address is one that goes straight to your support team (or at least forwards to them). You don’t want to discourage your subscribers from responding to your message by using a no-reply address, such as noreply@your-domain.com, because replies are part of the engagement metrics that some email service providers (Gmail, for example) use for determining the importance of your email and whether it belongs in the inbox or spam folder.

Another consideration is that customers will sometimes request removal from a mailing list, and if they see noreply@your-domain.com they are more likely to hit the “Spam” or “Complain” buttons instead – complaints are the worst form of engagement you can have on your email campaigns.

Lastly, no-reply addresses run a greater risk of being sent automatically to the junk folder. As this GlockApps article states, “Some ISPs, network spam filters, and customers’ personal email security settings are set up to move messages with ‘no-reply’ addresses to the junk folder.

In short, if you care about your email campaigns’ engagement rate and future deliverability, specify a meaningful sender address for and avoid using a no-reply email address.

5. Use a descriptive Sender label

While a clever subject line can certainly help you stand out in a crowded inbox, your subscribers will still need to recognize your brand’s communication when they scan their inbox. You don’t want them left wondering why they’re getting an email from someone they don’t know with a cryptic subject line that promises to solve pain point XYZ.

Consider these three basic options for sender labels:

  1. Brand or Product Name
  2. Brand or Product Name + Function (e.g., Support, Sales)
  3. First Name at/from [Brand or Product Name]

With the third option, consider the name of the person as well as your product name. Is your product name a single word, one to two words or longer? Will the entire label fit in the “From” field? Whatever format you choose, make sure to be consistent across all of your sender accounts and test for appearance before you start using a new sender label.

6. Use preview (aka preheader) text

While it isn’t always a visible element of your email’s design, preview text provides valuable real estate to expand your message. You should think of it as a second subject line – an additional opportunity to convince your recipients to open your email. The better your open and engagement rates are, the better chance you have of landing in the inbox. Many platforms, including BigMailer, support specifying this text. If your platform doesn’t support it, you can still have a preheader element as part of your email template design.

7. Test emails with spam tools

Testing every email adds an extra step, but it’s an incredibly important one. Because testing typically has to happen outside of an email marketing platform using tools provided by websites like Litmus, Email on Acid or GlockApps, you may be tempted to skip it. You shouldn’t – it may mean the difference between your message being successfully delivered or it being flagged as spam.

With that said, even experienced marketers using these tools can’t avoid landing an email in the spam folder every once in a while – this is especially true for Gmail and is often due to the topic of the message.

Starbucks email in spam folder

Example of a high-quality email and sender in spam folder

Don’t stress – if the occasional email gets a low engagement rate because a few spam keywords made it into your message, know that you are not alone. It’s become necessary at this point for email marketing platforms to embed email testing into their platforms to simplify a marketer’s campaign workflow. This is exactly what the team at BigMailer is currently working on, and we hope to delight our customers with this workflow improvement soon.

Relative engagement

Mailbox providers keep track of how your email recipients interact with your emails, so you need to maintain a high engagement to achieve a high inbox placement rate. Consider these tactics:

  1. Periodically remove unengaged subscribers from your list. Identify anyone who hasn’t engaged with (didn’t open) your emails for 90 or 120 days and either permanently remove them, or exclude them from your frequent mailings (you could send them your highest engagement/appeal content or only critical service notifications regarding their accounts).
  2. Send emails with appealing call-to-actions (CTAs) and make it necessary to click and interact with your email. It may seem obvious, but it’s not uncommon for some marketers to include phone numbers to place orders or have the website address in giant font to make it memorable, which may push a user to simply type the address when they are ready to place an order instead of clicking on a link in an email (and for a marketer to correctly attribute a conversion or sale to the email sent).
  3. Engage in email exchanges with your customers using the same email address that you use to send emails, or at least using the same sender domain, for example for customer service inquiries. Any email interactions between your and your customers signal trust to mailbox providers.

Consider using a dedicated IP address

IP (internet protocol) address is a unique address that identifies a device (computer or server) on the Internet or a local network. When you start using a hosted transactional or bulk email marketing service, by default, your emails are being sent from a group of servers with different IP addresses, and that group of servers is shared by multiple senders like you. So your emails use a “shared IP pool” and the reputation of those shared IP addresses is shared as well.

The biggest factor in IP reputation is whether it’s blacklisted, which happens when emails sent from a given IP get flagged as “Spam” by the recipients. If the % of complaints is high enough, the IP gets blacklisted and may get blocked by ISPs.

You can benefit from a dedicated IP address IF:

  • You are looking for a fresh start and looking to invest in building a strong email sender reputation
  • You have a small list now, but plan to grow it fast and monetize it, while controlling cost and ROI by using a low cost provider
  • You have built up a sizable list (over 20,000 subscribers) and ready to engage it with high quality content

Unfortunately, low volume senders are limited in their options because most low cost bulk email marketing service providers don’t offer an option to get a dedicated IP address on lower pricing tiers. And if you use an ESP that does offer access to a dedicated IP, it may come with a hefty price tag (for example $250 per IP at ConvertKit). If you use an ESP that runs on Amazon SES, like BigMailer, you can request a dedicated IP(s) from Amazon anytime, at a cost of $25 per IP per month.

Manage sender reputation – keep complaint rate low

Just like with an IP reputation, the sender reputation is affected by email recipients marking the emails as “Spam”. An industry benchmark is to keep complaint rate below 0.1%, but it’s more nuanced than that. The lower the volume of sending the less sensitive a mailbox provider is to the complaint rate, due to statistical insignificance (just 1 complaint can change the ratio dramatically). High volume senders have to be more vigilant – being close to the 0.1% ratio can trigger a manual campaign review from an ESP they use and can be followed by an account suspension.

A site/domain can also be blacklisted as unsafe with various monitoring services, like Google Save Browsing. You can monitor your domain/IP health by signing up with various providers, like Google Postmasters, or blacklist monitoring services.

Manage your sender domain identity

While this step is optional with most email service providers and requires a little more technical knowledge than the other items in this guide, most email platforms allow you to configure Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) for your domain to help improve your sender reputation by making it appear more authentic and safe. We highly recommend getting both SPF and DKIM configured for every sender domain you use to send emails. 

Use a different sender domain and IP addresses for any cold email campaigns, which have the lowest engagement and can burn your sender reputation. You may want to consider using a different sender identity for your marketing and transactional emails as well, to ensure your transactional email delivery doesn’t get affected by your bulk campaign practices.

Did you find this article helpful? Were you able to find a few useful practices to include in your email campaigns? Please leave a comment – I would love to hear from you.

 

How to Create a Zapier Integration

Using a Zapier integration you can connect BigMailer to hundreds of other platforms and applications. You can sync up your customer records with a CRM or another ESP, or add records to BigMailer when you acquire subscribers or customers in other platforms.

Below is a list of actions and example scenarios that can be setup.

IF [something happens elsewhere] > Add a contact to BigMailer brand

Examples:

IF a new response is collected via Google Forms add a contact into List [some-name] in BigMailer

IF a new row added to Google Spreadsheet add a contact into List [some-name] in BigMailer

IF a new contact is added in [some other ESP] also add a contact into List [some-name] in BigMailer

IF a new customer/sale/order is added in [some platform] add a contact into List [some-name] in BigMailer

IF a contact is added in BigMailer > DO [this action somewhere else].

Examples:

IF a new contact is added to List [Member] in BigMailer also add a record in [some platform].

IF a new contact is added to List [Paying Customer] in BigMailer send a message via [Gmail/Slack/other].

How to Create a New Zap with BigMailer

Log into Zapier with your account, then go to this page and click on “Accept Invitation & Build a Zap”.

When you choose an app in either step 1 or 2, search for “bigmailer” (no space) then select a BigMailer app listed.

Zapier: find BigMailer app

Zapier: find BigMailer app

Once you select the action, you will be asked for an API key to complete the step and a link to the page to copy API key will be provided.

Zapier: authorize BigMailer with API Key

Zapier: authorize BigMailer with API Key

Need an action not listed? Reach out to us via chat to request it.

 

How to Export and Delete Contact Segments

There are many reasons why you may need to export your lists or segments, let’s review most common use cases and best approach.

  1. GOOD. Identify and delete unengaged contacts. This is a good practice – removing unengaged emails, for example anyone who hasn’t opened your emails for 90-120 days, from your list to improve engagement and protect your sender reputation, as long as you exclude those contacts that were added to your list recently (and haven’t had a chance to engaged yet). Low engagement leads to lower inbox placement overtime.
  2. GOOD. Update or sync your unsubscribe, bounces, complaints with internal database or another platform, e.g. a CRM.
  3. BAD. Delete your unsubscribes and bounces to reduce overall list size and cost associated. BigMailer uses this data to ensure no emails go out to these email addresses, so if you accidentally bring those records back onto the platform you are risking a) those who unsubscribed will hit complaint/spam button, which will negatively affect your sender reputation b) high bounce rate on any campaign or over a time period can affect your future deliverability and inbox placement.  If you have very tight control over your list management and re-importing bounced email addresses isn’t a possibility then removing old bounces may be ok. Typically, unsubscribe rate is very low so removing those records is more risk than it’s worth to save a small % of the monthly fee.

NOTE: BigMailer doesn’t allow you to remove contacts that were sent an email in the last 30 days. That’s because when a contact is removed from BigMailer account, the Unsubscribe page no longer works for the removed email address, so the email recipient is more likely to hit Complaint/Spam button, which hurts sender reputation.

How to Export a Segment

First, go to the Lists tab in the site header to see all your Lists. Click on the arrow down link on the grey button next to the List you need to export.

list export

Give your export a name that will help you recognize it later on – recent exports will be stored for you in a list. If you need to export only a segment of your list, click on the checkbox above the Create button, to load the segmentation options.

You will most likely need to define a new segment for the export.

Export Unengaged Contacts

Make sure to add a condition to exclude those contacts that were added to your list recently, if you plan to remove Unengaged contacts. Recently added contacts are most likely to engage with your content, so it would be a costly mistake to make to remove them.

Once you define the segment, click Create. Depending on the List or segment size, a link will be generated within seconds or minutes for you to download your data as .csv file.

list export download as csv

How to Delete a List

Delete a ListFollow these steps to delete any List:

  1. Go to Lists tab to see all you Lists
  2. Click on the arrow down icon on the button next to the List

You will have 2 options:

  1. To delete a List only, this means only the label will be deleted from the list view, all the contacts in the list will remain unchanged.
  2. To delete the List and all contacts in that list, by checking the box next to “Also delete all contacts in this list”. Delete contacts
  3. If you choose this option, all contacts in this list will be removed across all your lists in a single brand. Contacts deletion will be scheduled for removal within 24 hours and appear as Pending until it’s complete.

How to Delete a List Segment

If you want to delete a segment, you need to create a segment, save it as a new List and then delete it:

  1. Create a new List, e.g. “Unengaged – 90 days” and import the csv file you downloaded into this new list.
  2. To stop sending to Unengaged contacts before the 30 days limitation expires you can simply “Exclude” the list from your Bulk campaigns.
  3. Follow the steps for deleting a List in the section above.

Got a use case we didn’t cover in this article? Let us know so we may expand it.

 

 

How to Manage High Volume Sending and Protect Sender Reputation

Experienced marketers know that smart volume management is part of the sender reputation management, especially for high volume senders. If your list is smaller than 5000 emails, then this isn’t something you need to worry about and as long as you build your list overtime and increase sending volume gradually.  Also, if you or your organization is a sender with an established reputation and a history of high volume sending, the volume isn’t as big of an issue as campaign engagement and future deliverability.

You need to carefully manage your sending volumes in order to build up your sender reputation if you are:

  1. Just starting out with bulk campaigns for yourself or a client, or
  2. Haven’t engaged your list of 5k+ subscribers in the recent months
  3. Switching your sender domain, email address, and/or provider, possibly due to a “burnt” reputation in the past.

Why not blast a single email campaign to your entire list? Because if this volume of sending isn’t typical for your sender identity it will look suspicious to a mailbox provider (aka ISPs) because big changes in sending volume may indicate that a list hasn’t been grown organically (naturally), bur rather rented, purchased, or harvested via other means, and this can have a negative impact on email deliverability and inbox placement. So what should you do? Start by sending low daily volumes and build up volume over time – the idea is to send less than 1k emails per day per provider when you are just starting out, and ideally start with high quality messaging and high engagement subscriber segments.

High engagement on your early bulk campaigns will aid your sender reputation score and improve inbox placement rates on future campaigns. 

There are a many different ways you can break down your list:

  1. Segment your list based on a field like “Date Signed Up”, “Order Date”, or similar date or number based fields that indicate subscriber recency or loyalty, and start sending initial campaigns to your recently engaged or your most loyal customers.
  2. Based on demographics like age or gender, or a number-based field like “Member ID” with “greater/less than” condition.
  3. Based on past campaign engagement, e.g. anyone who “opened” any campaign in the last 14-21 days.
  4. Segment your list based on location. If you customize campaign send time based on subscriber local time you can get better engagement. The best time to send on week days is usually 6-10am local time.
  5. If bulk of the emails on your B2B list are not major providers, you can actually send a large campaign by simply segmenting out the top providers using an email domain check, e.g. if “domain is” or “domain is not”. See example in the screenshot below.

    segmentation based on email domain

    Segmenting based on email domain in BigMailer

Depending on your list size, you may choose to use and combine several of the methods listed above, and that’s perfectly fine. There is no one size fits all approach to building your domain reputation – you know your list best and can figure out the best strategy for yourself.

It may be frustrating to not be able to send to your entire list and put in all the extra effort, but the effort is worth it and will pay off via better long term deliverability, inbox placement, and most importantly your subscriber engagement with your email campaigns as a result.

Dedicated IP for Email Marketing – Do You Need It?

Dedicated IP for Email Marketing – Do You Need It?

If you work with email marketing campaigns you no doubt heard about dedicated IP (internet protocol) addresses. Perhaps you have been wondering about who uses them and whether you should considering using one yourself. In this article, we explain what they are for and list some reasons for when it makes sense to use them.

IP (internet protocol) address is a unique address that identifies a device (computer or server) on the Internet or a local network. When you start using a hosted transactional or bulk email marketing service, by default, your emails are being sent from a group of servers with different IP addresses, and that group of servers is shared by multiple senders like you. So your emails use a “shared IP pool” and the reputation of those shared IP addresses is shared as well. The IP reputation is one of the factors that influences email deliverability and inbox placement.

About Shared IP Pools

Email service providers (ESPs) are responsible for managing (and protecting) the reputation of the IP addresses used by their platform. For that reason, many ESPs turn away customers if/when they determine that their use of the platform may negatively affect other customers. Some platforms (like Mailchimp) scan the email lists customers upload to automatically determine its quality and can suspend account or campaigns based on that data. Many providers have a manual campaign review step for all new customers, so it’s not even possible to send a bulk campaign as soon as you sign up. This type of customer filtering and platform protection by market leaders results in 2 things:

  1. Desired customer pool with high quality email sending practices
  2. Higher prices for the service, in return for better IP reputation

So when you use a market leader like MailChimp or ActiveCampaign, that cost up to x10 more than some of the lower cost providers, you pay for “good company” in addition to extra features (e.g. multivariate testing, landing pages, email template variety). However, the biggest factor in IP reputation is whether it’s blacklisted, which happens when emails sent from a given IP get flagged as “Spam” by the recipients. If the % of complaints is high enough, the IP gets blacklisted and may get blocked by ISPs. If the shared IP address  isn’t blacklisted, the quality of senders you share it with doesn’t make as big of a difference.

Does it mean that low cost email providers have lower quality IP pools than market leaders? Yes, it does. Does it mean all your emails will go to Spam folder? No. Not if all other email deliverability factors signal quality.

IP Reputation as an Email Deliverability Factor

Lets review the factors that affect deliverability, they are:

  1. IP reputation
  2. Sender reputation (e.g. sender being your domain or exact email address the emails are sent from)
  3. Server and domain configuration (DKIM, SPF, etc)
  4. Global engagement
  5. Content and format of the email (spam words in subject or message body, format – use of images, etc)
  6. Relative engagement for you (sender) versus other senders in the recipients inbox
email deliverability factors

Email deliverability factors

On the diagram above, the green box represents factors that vary and change more with each campaign sent and the square on the left with 4 factors are not subject to dramatic changes on a per campaign basis. So with IP address reputation being only 1 of several factors, it can be a deciding factor in inbox placement but it depends on the quality score of the other factors.

Who Benefits from a Dedicated IP?

So if you are a sender with established good reputation and high engagement history, and especially if you are sending low volumes of emails (less than 5,000 per day), you have a low risk of being affected by a switch of ESP from a market leader to a lower cost provider. However, getting a dedicated IP address can help ensure your ongoing high deliverability in the future, when mailbox providers adjust their inbox placement algorithms.

If you are a high volume sender (send more than 10,000 emails per day) and perhaps have been experiencing deliverability issues with your current provider, switching ISPs might not give you an instant improvement unless you change some of the factors as well – improve list quality by removing invalid addresses, properly configure your domain for sending emails, invest in testing your email templates.

You can benefit from a dedicated IP address IF:

  • You are looking for a fresh start and looking to invest in building a strong email sender reputation
  • You have a small list now, but plan to grow it fast and monetize it, while controlling cost and ROI by using a low cost provider
  • You have built up a sizable list (over 20,000 subscribers) and ready to engage it with high quality content

Unfortunately, low volume senders are limited in their options because most ESPs don’t offer an option to get a dedicated IP address on lower pricing tiers. And if you use an ESP that does offer access to a dedicated IP, it may come with a hefty price tag (for example $59 per IP per month at MailGun). If you use an ESP that runs on Amazon SES, like BigMailer, you can request a dedicated IP(s) from Amazon anytime, at a cost of $25 per IP per month. Check out our comparison of bulk email marketing services to see how different providers accommodate use of a dedicated IP address.

If you are curious, yes we use a dedicated IP at BigMailer, and our total list engagement is at 70% with typical open rates on weekly campaigns in the 30-60% range. More importantly, we have seen open rates for gmail (very hard to place into inbox), as high as 80%.

Have you recently switched ESP and experienced a big change in inbox placement? Share your experience in the comments or via live chat. If you are a BigMailer customer we would love to use your story for a case study.

Happy email marketing.