Email Best Practices

Email deliverability provides feedback on whether you're sending the appropriate material to the right people at the right time. Email interactions like clicks, opens, and spam complaints all add to your email sending reputation. Positive engagement rates increase your chances of reaching the inbox rather from being trapped in a spam filter.

Let us now understand some of the best practices in order to increase email deliverability

• Maintain a good IP reputation: Your sending IP reputation is based on many factors, including (but not limited to) bounce rates, blacklisting, spam complaints, and lack of sending IP history. If you are buying a new IP it is necessary that you warm it up before sending it to the entire list of leads in order to gain the trust of the ISPs.
• Avoid Interactive Content (Forms, etc). Using Interactive content such as video, forms, Flash or Java embeds can cause your emails to get tracked by spam filters. Most email clients do not support them and hence it is suggested to use an image instead with a play button on top of it that redirects your recipient to your video.
• Don’t Use Spammy Formatting: i.e. Writing in all caps, Using the exclamation
  points in the subject line, Mixing letters, Symbols, and numbers to spell words, Using several font colors, sizes, or styles, and Using large font sizes. It could be tempting to populate the subject line in all caps in order to garner attention, however, this would instead lead to your emails being marked as spam by your leads.
• Keep the Image-To-Text Ratio Low: Too many images or too large of an image compared to text in an HTML email can make your message look spammy to a filter. Using an overwhelming amount of images under your email template tends to end up in the recipient's spam folder instead it is suggested to use images of less size while also making sure that the visual integrity is intact.
• Avoid Click Tracking unless you know you’re whitelisted. If you have not already enabled SPF and verified your DKIM records, you risk falling victim to impersonation or spoofing (The ISPs would feel that you are not who you say you are and thus falling under their crosshairs.
• Include Physical Address and a Way to Opt-Out.
• Don't use spam trigger words and phishing phrases like WIN, Free!
• List hygiene is key to getting past spam filters. If you send emails to unengaged or invalid contacts who ignore your emails, filters assume you're sending spam.
• Never use deceptive headers, From names, reply-to addresses, or subject lines.

You can check if your mail server IP is listed on some Spam Blacklists: MX Toolbox, DNS Stuff, Sender Score.