Planning on sending an email blast to your entire email list? Unfortunately, this practice can be risky and may cause you to end up on an email blacklist.

Email blacklists are notoriously challenging to get off of and require more resources and time than you may imagine. So, it’s worth it to take some extra time and precaution before you press send. If you find yourself in that situation where you need to send a mass email, follow the best practices below to reduce your chances of becoming blacklisted.

Email blast tips

Only send your email blast to subscribers who opted in to receive your email. If you are sending unwanted email, your recipients may not only ignore your emails, they may also mark the email as spam. If this happens enough, you just might be blacklisted. If your subscribers have stated how often and what types of email they want to receive only want a certain type of email (perhaps in your preference center)–respect that. How do you ensure that you are sending wanted email? Use double-opt in methods when people sign up for your email list and once they are signed up, create a preference center so they can decide exactly what emails they receive.

You’ll also want to scrub your email list of inactive users on a regular basis. These users may have been interested in your emails at one point, but if they haven’t opened an email from you in a few months, it’s time to set them free. Actively monitoring your engagement levels and removing those who don’t engage with your emails in a few months improves your sender reputation and reduces your chances of landing on a blacklist.

Don’t include attachments in your emails. Internet Service Providers (ISPs) are suspicious of attachments and it’s best to just not use them in your email blasts. Also consider that attachments in email blasts will likely be missed by recipients. Instead of an attachment, consider linking to whatever you’d like attached in your landing page copy (which is easier to track and attribute anyways).

Authenticate your email with SPF, DKIM and DMARC. Sender Policy Framework (SPF) verifies identity. Domain Keys Identified Mail (DKIM) ensures the message wasn’t tampered with during transmission. And Domain Based Authentication Reporting and Conformance (DMARC) requires that both SPF and DKIM pass in order to authenticate. These are all protocols that prove to ISPs that you are who you say you are.

Read more about how email authentication works and the differences between SPF, DKIM, and DMARC.

Check your reputation and blacklist status on a regular basis. You’re not going to receive an email telling you you’re on a blacklist. More likely, you’ll notice that your email is not being delivered to any of your recipients. This will cause you some time to search around to try and find which list you ended up on. There are numerous online blacklist checkers. Check out some of your options here.

If you’re following the tips above, your email blast has the best chance of a) resonating with your readers and b) protecting yourself from blacklists. Our email sending mantra here at SendGrid is to send the right message, to the right person, at the right time, and with the right frequency. If your email marketing situation calls for a large email blast, cross check with our mantra as well as our tips to avoid blacklists.

For more information on sending email that your subscribers crave, check out SendGrid’s 2017 A-Z Marketing Guide.



Kelsey Bernius
As a senior content marketing manager at SendGrid, Kelsey oversees the SendGrid Delivery blog. Her downtime is dominated by either her mountain bike or skis (depending on current weather forecast)–and mixing up a salty marg afterward.