1. Clean Up Your List
Remove addresses that are no longer valid, contain typos or just continue to bounce. The resulting list will contain emails that are active and receptive to the messages you send, which should significantly improve your open rate.

2. Grab Their Attention
Make the subject line interesting and pithy, and be sure to A/B test (sending two different versions to similar recipients to see which version fares better). Try different formats and phrases to see what works, and when possible, personalize it with the recipient’s first name. Also add appropriate details, including the offer and product name, while keeping it to the point.

3. Provide Quality Content
Send emails with information that’s interesting and relevant to the recipients. While information about an upcoming sale or new product is acceptable, bundle it with something of value, such as business tips and industry research. Also, keep branding consistent across all messages. 

4. Test Delivery Times
Send messages when recipients are likely to be checking their emails. During business hours is best – aim for the start of the workday and toward the end of the lunch hour, when people are returning to their desks. Recent research from GetResponse email marketing software found that open rates were highest on Tuesdays and Fridays.

5. Avoid Spam Filters
Spam filters have become more sophisticated, increasing the chance that your message won’t be seen by the recipient. Make sure all recipients have actually opted in to receive your emails, ask subscribers to add you to their address book, steer clear of overly sales-y language and avoid deceptive subject lines. 

6. Get Mobile-Optimized
Be certain that the site your email is promoting is mobile-optimized. Mobile use is increasing dramatically, meaning people are very likely to open your email on a phone or other device. If the site isn’t mobile-responsive and is hard to read, recipients will stop opening the email.