How do you find the sweet spot? The best way is to monitor statistics from your email blast software. See how many recipients open your emails, how many click a link, and how many unsubscribe. (Pay attention to the type of recipient, too, as your open rates for loyal customers will be different from new prospects.) Learn what works, make changes, and test again.
Be sure to look at the tech support offered by each of these companies, as we felt many weren't as available as we would have liked. You'll find that some offer 24/7 phone support, live chat, and email help, while others leave you to rely on online documentation and limited live support hours. The best services offer a combination of self-serve help resources—where you can search FAQs and articles to find your own answers—as well as live support via chat or phone when you can't solve an issue yourself. We cover all of these concerns in our reviews, plus you can get an overview in the feature chart above.
Note: If you want to attach additional files, such as a .pdf, we recommend that you store these files on a cloud storage service, such as Dropbox or Google Drive, and linking to these files within your blast. We do not support file attachments to an email blast as these file types tend to be larger, increasing your chances of triggering spam filters and preventing your blast from reaching your recipients.