How to Improve Email Deliverability on WordPress.com and Avoid the Spam Folder

Just because you send an email doesn’t mean that the intended recipient will ever see it. Some email providers may redirect it to a promotional, spam, or junk mail folder, or worse — completely block the email. Why? They’re trying to protect users from spam and phishing schemes and prevent inboxes from overflowing with unwanted emails.

Since email is an important way to interact with your followers, clients, and customers, you want to make sure that your emails don’t end up being flagged as spam or rejected entirely. While you can’t ensure that every single email makes it to a subscriber’s primary inbox — after all, recipients still have the final say over where emails end up — there are things you can do to improve your email deliverability.

In this article, we’ll talk about the three different types of email you might send, and the steps you can take to make sure that they almost always end up in recipients’ inboxes.

Three different types of email

There are three basic types of emails that most website owners will send from their domain — hosted emails, transactional emails, and marketing emails. They’re often sent by separate services, but not always. They may each require their own DNS records, depending on your circumstances, and have their own considerations for ensuring deliverability.

Hosted emails

Hosted emails are either personal or business emails that you send from an email service provider (ESP) — like WordPress.com-hosted email, Google Workspace, or Outlook — using your website’s custom domain. 

These types of emails are generally one-on-one communications or messages to small groups of people. They’re the types of emails you use to schedule meetings, solve customer service issues, send and receive files, and communicate internally with your team.

Transactional emails

Transactional emails are automated emails that are sent when an action is completed on your website. Examples of transactional emails include:

• Purchase receipts
• Account confirmation/verifications
• Password resets
• Form submission confirmations
• Subscription renewal notifications
• Credit card expiration notifications

In WordPress, transactional emails are sent either by WordPress core (e.g. password reset requests and account verifications) or by specific plugins that you’re using on your site. Contact form, eCommerce, forum, or membership plugins are all common types of tools that would need to send out transactional emails to users. 

The mechanism that sends these emails can either be the WordPress native wp_mail() PHP function or an ESP, in conjunction with a secure mail transfer protocol (SMTP) plugin.

Marketing and promotional emails

These are emails sent to a list of people who have subscribed. They can be sent manually or be automated based on subscriber activity on your website or within an email campaign. The key distinction between marketing emails and hosted and transactional emails is that they’re specifically designed to convert subscribers in some way. 

For an eCommerce site, marketing emails are used to drive sales. For a neighborhood newsletter, marketing emails may simply be used to inform people of upcoming events and encourage community participation. Just because they’re marketing emails doesn’t necessarily mean that they’re commercial in nature. However, they are distinct from transactional and hosted emails in that no transaction needs to happen for them to be sent and received, recipients must be subscribed, and communications are not usually individualized.

eCommerce email example from Really Good Emails

Most marketing emails are sent using third-party platforms like MailPoet, Mailchimp, Constant Contact, and Zoho. Some of these platforms also offer transactional email and some are strictly geared towards marketing emails. 

Ten tips for improving email deliverability

So, how do you actually ensure your emails will get delivered to recipient’s inboxes on a consistent basis? Follow each of these tips for best performance.

1. Make sure your IP address isn’t blocklisted

If your website is hosted on a shared server and you’re sending transactional emails using the native WordPress wp_mail() function, you’ll definitely want to make sure your website’s IP address isn’t on any blocklists. You might want to also check this for your marketing and hosted emails, but IP addresses that end up on blocklists are most often shared hosting provider IP addresses. 

When you host your website on a shared server, you’re sharing that server with a number of people that you don’t know and you have no control over how they use that server. If they send out spam emails from your shared server, the IP address may get blocklisted. Since you’re sharing that server space, your website and emails coming from your website could be affected and flagged as spam.

You can check your IP address using tools like MxToolbox. Keep in mind that there are some blocklists, like UCEPROTECT, that are scams, where they include every IP address they can find, and you have to pay to have yours removed. If you see your IP address on this phony blocklist, you can safely ignore it, as it shouldn’t actually affect your email deliverability. 

However, if you do see your IP address on a valid blocklist, you’ll first want to do a security scan of your website to make sure it hasn’t been compromised, reach out to WordPress to see if any domains on your shared IP are the source of the blocklist, and reach out to the blocklist itself to find out how to get your IP address removed. 

2. Use an SMTP plugin for transactional emails

While wp_mail() is the native mail function in WordPress and generally works to send emails, it doesn’t include any authentication information, which can lead to your emails being flagged as spam. 

Instead of relying on WordPress’ native PHP function, send transactional emails using a third-party transactional ESP along with an SMTP mail plugin like Post SMTP Mailer/Email Log. Note that you do need to have a WordPress plugin-enabled plan with WordPress.com to install plugins.

3. Verify your email’s identity with SPF, DKIM, and DMARC records

Since spammers and hackers can easily impersonate domains when sending out phishing emails or other scams, it’s important that your emails are authenticated and verified as truly coming from your domain. To help keep spoofed email out of inboxes, mailbox providers (like Gmail) will look for Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication Reporting and Confidence (DMARC) records that confirm that the email is coming from the domain that it says it’s coming from.

If an email doesn’t pass SPF, DKIM, and/or DMARC, email servers may block those emails or send them to the spam folder. If your emails are experiencing deliverability issues or being flagged as spam, then you might want to check that you have these records set up correctly in your DNS.

If you’re using WordPress.com for hosted email, see instructions for adding the correct records to your DNS. If you’re using another ESP for your hosted, transactional, or marketing emails, you should get directions from their help center on what records to add to your DNS and how to add them.

If your domain’s DNS is hosted with WordPress.com, there are instructions for adding external mail records in the support center.

Note: If you’re using a single top-level domain to send email but a different ESP for hosted, transactional, and marketing emails, you’ll need to combine SPF records into one single SPF record. Each domain can only use one SPF record. 

4. Send marketing and transactional emails from separate subdomains

While this isn’t necessarily a must, sending different types of emails from separate subdomains can help protect your email deliverability. Instead of sending all your emails from yourdomain.com, you might send your hosted emails from yourdomain.com, transactional emails from accounts.yourdomain.com, and marketing emails from mail.yourdomain.com. 

The primary reason for using subdomains to send your transactional and marketing emails is to keep their sending reputations separate. If one sending subdomain becomes blocklisted, it won’t affect your entire domain. 

Not sure how to set up a subdomain? See our documentation for instructions.

5. Use IP warming for marketing emails

IP warming is a four to six week period of scaling your sending volume for marketing emails to avoid issues with sending reputation. This is especially important if you have a large email list and are sending emails from your IP address for the first time. 

If you start off by sending tens of thousands of emails to your entire list, this may result in a lot of hard bounces, unsubscribes, and spam reports. If you start with smaller chunks of your list at a time, you can slowly weed out invalid addresses and people who don’t want to receive your emails without as much impact on your list reputation.

6. Practice good list hygiene 

Make sure you’re sending emails to the people that want them in the first place:

• Don’t ever buy lists. Lists may include addresses not in your target audience and hidden spam traps. If the people you’re emailing didn’t ask to be on your list and aren’t interested in your product, they may report you as spam at very high rates. Spam trap email addresses may get your sending domain blocklisted. Either of these effects can drastically reduce your deliverability.
• Don’t subscribe people who didn’t opt in. Just because a customer received a transactional or personal email doesn’t mean that they want to be subscribed to your newsletter. If you add people to your mailing list that didn’t specifically ask to be added, you increase the risk of spam complaints.
• Use double opt-in or confirmed opt-in. Single opt-in is where someone agrees to receive an email by filling out a sign-up form or checking a box during checkout. Double opt-in sends the subscriber an additional email asking them to verify that they did, in fact, mean to subscribe. While double opt-in seems like more of a hassle, it helps prevent spam sign-ups and accidental sign-ups. 
• Segment lists. Segmenting your list into groups based on interests, past purchases, geographic location, and other data points will allow you to send more targeted emails to people. If your emails are highly relevant to your audience, they’re less likely to unsubscribe or report your emails as spam.
• Delete inactive subscribers. Before you delete your inactive subscribers, you might attempt to re-engage them with some special offers, but if that fails, you’ll want to remove them from your email list. There’s no reason to pay for subscribers who are not responding to your outreach efforts.

7. Follow the CAN-Spam Act

CAN-Spam regulations set the rules and requirements for commercial messages and give recipients the right to unsubscribe from email lists. It also provides a list of penalties for email senders that violate the CAN-Spam Act’s policies. Aside from the legal implications of violating any of these policies, such violations can impact your email deliverability as well.

Avoid legal pitfalls and deliverability impacts by following these guidelines:

• Use your website’s domain or subdomain to send email. If you send email from a personal email address or include a “reply-to” address that uses a different domain than your “from” address, you may get flagged as spam, blocked, or blocklisted.
• Don’t use deceptive subject lines. The message in your email body should reflect your message’s subject. Besides potentially getting marked as spam, your recipients would likely be confused if your subject and message don’t match. You could end up with poor conversion rates and lots of unsubscribes.
• Include an address for your business at the end of your emails. This can be a PO Box or street address, but it should be a registered address for you or your business.
• Include an opt-out link in your email footer. Subscribers should be able to easily opt out of your emails directly from each message they receive. You can also offer settings so that subscribers can choose to receive only certain types of emails, rather than unsubscribing entirely. Giving recipients a way to quickly unsubscribe or change their subscription settings will help prevent spam complaints.

8. Use email best-practices for content and sending frequency

While you want to send emails often enough to keep subscribers engaged, you want to also make sure that you aren’t bombarding recipients with too many emails — especially ones that aren’t relevant to their interests. You also want your emails to be short and to-the-point to ensure maximum engagement. 

The following tips will help you stay out of the spam box:

• Don’t put marketing messaging in transactional emails. Transactional emails should be for informational purposes only. Adding marketing messages to your transactional emails can get them flagged as spam. If you want to provide marketing messaging to a customer after they make a purchase, consider using a triggered email that is sent based on the product or category that the customer purchased or adding custom messaging to your “thank you” page.
• Don’t use image-only emails. Not only are image-only emails often flagged as spam, they’re not very accessible. If someone has a visual impairment, they might not be able to read your message in an image-only email. Also, many email clients automatically block images in emails and recipients have to click a “load images” button to get images to display. Allowing recipients to read your message and click on call to action (CTA) links without having to load images will keep your emails more accessible and improve conversions.
• Avoid sending large email attachments. Whether you’re sending hosted, transactional, or marketing emails, you don’t want to send ones with large embedded images or attached files. Some email clients have file size limits on incoming and outgoing mail, and large file sizes may also trigger spam filters.
  Also, avoid attaching file types that are not pdf, jpg, png, tiff, or gif image types. File extensions like zip, avi, swf, and exe are all more likely to be marked as spam. 
• Don’t send too many — or too few — emails. It’s important to establish a regular sending schedule. One email a week is a good policy. Conversely, you don’t want to send too few emails or your list will get stale, and your fans might forget about you. If you haven’t sent an email in many months, you might find that subscribers have discontinued use of their email address, fans have lost interest in your brand, or your emails are suddenly ending up in a “promotional” box that gets checked infrequently.
• Use your brand name as your “from” name. By using your brand’s name as your “from” name in your emails, you’ll ensure that recipients know the email is from your company rather than mistaking it for spam. If you want to further personalize your subscribers’ experience, you can add a brand representative’s name to your from email like, “Samantha from YourSite.com.” 
• Send relevant content to the right list segments. Even if you segment your list, those segments won’t be useful if you mostly send mass emails to your entire list. Make sure to engage different segments of your list in different ways that are relevant to their interests, location, and purchasing habits. For instance, if you’re a sporting goods store sending out holiday sales promotions for Christmas, you may want to promote a sale on skiing equipment and warm outerwear for your customers in cold, mountainous regions. For your customers in Australia, where December and January highs can range from 70-90°F, you may want to promote a sale on swimwear and pool accessories.
• Consider personalizing your emails. Personalized emails have between 25-29% higher conversion rates than generic emails. If your subscriber list includes names in addition to email addresses, it’s a good idea to use your ESP’s merge tags to add personalized messaging like, “Hey Tony! Get your patio ready for summer with 20% off all grills and accessories!” to the subject lines and body copy of your emails. 

9. Ask recipients to whitelist your domain and IP address

Some email clients can be extra aggressive in categorizing email as spam. As a last resort, you may want to ask recipients to whitelist your sending email address, domain, or IP address to make sure that the mail client knows that you’re an approved sender.

Improving email deliverability is tough work, but it’s worth the effort

Ultimately, recipients have control over where emails end up. If they mark your emails as spam or they choose to consign them to the “promotional” folder, there’s nothing you can do to prevent that. But by following the suggestions above, you can make sure that your emails start off in the inbox before recipients decide to route them elsewhere.

Using reputable hosted email and transactional and marketing ESPs in conjunction with the correct domain authentication records will go a long way to ensuring emails don’t get flagged as spam or blocked completely. Making sure your messaging is targeted, is delivered on a regular schedule, and complies with the CAN-Spam Act will take you the rest of the way towards a good sending reputation and high email deliverability.