But there are a few industry insights that will ensure that your emails do not get trapped in the spam folder and improve your email deliverability routine.

1. Use a custom email domain

If you are using free email clients like Gmail, Yahoo Mail, or Hotmail to send informational emails and to market your products or services, you are already looking like spam.

To be honest, no one these days opens business emails that come from Gmail. They directly go to the spam folder. Free services like these are not designed to send thousands of emails, so they get flagged as spam.

Other than this, several email service providers just reject these generic emails. They only entertain custom domains that are verified by the users. For example, I had previously tried to register on Mailchimp with my personal email ID, and it asked me to provide a business email ID, which should be on a custom domain.

Having said that, several business emails that people receive as spam are sent using compromised Gmail or personal email accounts, which is the reason why when business emails are sent using domains such as Gmail and ymail etc they get flagged as spam faster than anything else.

2. Build an email reputation for better delivery

Use Email Service Providers which are actually famous for this. Popular brands like Mailchimp, SendPulse, etc., are a few reputable email service providers. These providers have a strong reputation with internet service providers and email clients, which helps ensure your emails are delivered to your subscribers' inboxes. I have personally used SendPulse, and it has options like spam filter, engagement checker, and bounce handling, which helps in getting proper insights about what is happening with your emails.

I usually get stats about; 

• how many email are sent, 
• how many are flagged as spam, 
• the unsubscribve rate and 
• how many emails are opened by users.

On the other hand, you also need to be cautious that not many people flag you as spam, or else your custom domain emails will be sent to spam folders. To maintain a good email reputation, it is important to follow certain best practices, such as;

• Sending relevant and engaging content,
• Ensuring to avoid spam trigger words like "free", "buy now" etc.,
• Only sending emails to users who have opted to receive them.

If you trick people to sign up, and then send emails, they will quickly block or flag your emails as spam.