Email Best Practices

The most important rules to follow on your way to the inbox

 

General best Practices

  • Always include a strong call to action
    • These generate much needed interaction with your emails which results an increase of your reputation and thus better inbox placement
  • Make sure your emails are easily recognizable.
    • Make sure your brand is visibly present in your emails
    • Try to use the same templates for your emails so they're easily identifiable by the users
    • Don't switch your sending domain too often
    • If you happen to make important changes to your mailings, announce them up front using your old style and let people know what to expect in the future
  • Make sure your emails render properly on all platforms, even mobile. Test this extensively before sending your campaign.
  • Don't use url shorteners (bitly,....) in your emails
  • Avoid click-bait subjects ("open now!", "unique offer!", "Buy now!",...)
  • Know your audience and send relevant and personalized emails
  • Offer a preference center where the user can adjust which emails and with what frequency he receives mails. This might help keep the user from unsubscribing
  • Test, test, test! Always test extensively before sending anything
  • Keep subject lines under 50 characters. Shorter subject lines have proven to generate more opens than longer subject lines

Images vs Text

It's important to find the right balance between images and text in the content of an email. Creating "all image" emails is a very bad idea. Here are some reasons why:

  • The text on images will not be as clear and crisp as actual html
  • Some providers don't load images by default, so without text your email will be blank
  • Providers will not be able to properly verify the content and may mark the email as spam
  • Because there is no actual text there will not be a proper text version of the email
  • Not every email client renders all image emails correctly. This is especially an issue on mobile devices.
  • All image emails will not show up in inbox searches
  • People on slower connections (mobile connections) might have trouble loading the email properly or it might take a long time. Additionally, it'll consume a lot more bandwidth than text
  • It's easier to alter text in an email than having to change the entire image
  • All image emails break easily, for instance when a user uses browser zoom
  • Images drastically increase the physical size of your emails. Some browsers such as Gmail will "clip off" your email at 120kb
  • Never hide calls to action under a graphical button! Many users will not see this button if their client doesn't load the images, so they won't know where to click and you'll lose very important interaction on your email•
  • A good rule of thumb would be to use about 30% of the available space for images

Sending Domain/Brand

  • Always make sure your domain is set up properly DNS wise. The following DNS records should always be present:
    • A-record
    • MX-record
    • SPF-record
    • DKIM-record
    • DMARC-record
  • Use a subdomain instead of the TLD
    • Subdomains make sure it's easy to configure the necessary DNS records and point them to our infrastructure
    • A subdomain adds an extra layer of security to protect the reputation of the TLD
  • Use different subdomains for different email streams. Keep transactional and bulk mails separate by using different subdomains:
    • Account.mailing.com
    • Order.mailing.com
    • Billing.mailing.com
    • Newsletter.mailing.com
    • Sale.mailing.com
  • Avoid using "no-reply" addresses
  • Every email should have an unsubscribe link!!!
  • Always make the unsubscribe link easy to find. If people have to look too long for the unsubscribe link, they will mark the email as spam which will harm your reputation and might eventually results into your emails going into the spam folder or worse, get you blacklisted.
    • Don't try to hide the link by giving it an unnoticeable color (black text on a black background for instance)
    • Don't use extremely small fonts
    • If possible, add the link to the top of your emails
  • Make the process easy and short
    • Use One-click unsubscribes. Clicking on the unsubscribe link in the email should lead to a confirmation page with a confirmation button. This should be sufficient to unsubscribe the user.
    • It is OK to ask for additional info on that page (why are you unsubscribing) or showing the user a preference center where they could adjust the email frequency instead of unsubscribing, but the one-click unsubscribe option should always be present. Also add a small message for the user "We're sad to see you go".
    • A good optout process should take no longer than 15 seconds for the user. This includes finding and hitting the unsubscribe button.
    • NEVER ask the user to log in or enter their password to be able to unsubscribe
    • Optout the user immediately in your system
    • Do not send a confirmation email to confirm the optout
  • Always include the header unsubscribe in your emails
  • Unsubscribe links in emails should remain active for at least 60 days after the emails was received
  • Unsubscribe processes should be evaluated on a regular basis to make sure the process is still working properly

Userlist - Acquisition

When acquiring new address in your list, keep the following in mind:

Use a double optin system. This way you verify the validity of new addresses and more importantly, it's the only way to make sure pristine spamtraps cannot enter your system and cause major reputation damage. It also protects your system against malicious entries.

Never buy or rent 3rd party lists.

  • There is no way to verify the validity of these emails. Even if they were valid addresses at some point, there is no way to determine how old they are and they might have been turned into recycled spamtraps.
  • These users don't know you and most likely don't want your emails, which results in a lot of spam complaints.
  • Using 3rd party lists isn't legal in the EU. You are only allowed to send to user who explicitly gave YOU permission to mail them or who you have done business with before

Userlist Maintenance

Always enable Email Quality on your lists and set it to "normal" or stricter. This will keep your list clean by removing inactive addresses.

Periodically run "re-engagement" campaigns

  • Target users which have been inactive for a certain period of time
  • Make them an offer to encourage engagement and restore the relationship
  • Give them an opportunity to unsubscribe
  • If the user still shows no signs of life, unsubscribe them

Content

  • Add alt & title text for every image: When images are not loaded, on mouseover, ... this text will be shown. Missing alt & title can increase spam score
  • Never use a probe/tracking link behind a visible link in the content: This can be seen as phishing
  • Try to limit different domains in email (including images) to a minimum: This can increase spam score and the reputation.
  • Try to use https links if possible: Better for reputation.
  • Try to avoid long links: This can increase spam scoring
  • Try to avoid hidden elements (hidden attribute, CSS or "white on white"): This can increase spam scoring
  • Try to avoid very small fonts: This can increase spam scoring

 

Email Size and Attachments

It is advised not to exceed an email size of 50 to 70Kb. Larger emails will probably get blocked. If possible don't use attachments in the email, especially if they are large, but add links to a Content Delivery Network or a video supplier such as YouTube.