How to send mass emails without getting blocked

Email campaigns are very effective, but only if you use them correctly. If not, you risk being blacklisted by Internet Service Providers (ISPs), recipients designating your messages as spam, or the communications failing to meet the ISPs' authentication standards, among other issues. 

Here are some tips to help you send emails without being blocked:


1. Use a trustworthy IP address 

A key concern for ISPs is domain reputation. Blacklisted profiles, spam reports, dwell time, and spam traps affect sender reputation. 

Furthermore, an IP address needs some time to ‘warm up’ before sending emails. This involves sending low campaign volumes to begin with and then gradually adding more as time goes on. You’ll then need to analyse how recipients interact with your emails by looking at open and click through rates.

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2. Set up SPF records

ISPs use Sender Policy Framework records (SPF records) to ensure that email campaigns are legitimate. This allows them to compare the sender’s stated ID in the DNS with the IP address. If the ‘from’ section is at the beginning of the SMTP dialog, the SPF record can be verified. However, if the source address in the ‘from’ section is unauthorised, the email will be rejected. 

Crucially, if the email address doesn’t have any SPF record at all, it may be caught by spam filters. 


3. Use double opt-in when admitting subscribers

This has become an email newsletter mechanism that ensures that a mailing list is legally obtained and actively used, adding another layer of protection against bogus emails and guaranteeing that your subscribers are genuine.

Adding a second signup step assures that your followers want to get your emails, whether you're delivering a newsletter, promotional offer, or notification about new products. This lessens the possibility of people unsubscribing from business email lists due to potential complaints about email spamming. 

Use double opt-in to get more qualified leads, create strong relationships with existing subscribers, and enhance email deliverability.


4. Optimise your email content

To avoid receiving spam complaints and being put onto an email blocklist, avoid sending marketing emails with overly generic messages. Where possible, use personalised content that appeals directly to your prospects’ and customers’ pain points. 

Mapping out customer personas can help you to do this, allowing you to then create tailored, valuable material that your audience can relate to. 


5. Include an unsubscribe link in every email 

Adding an unsubscribe link allows your customers to withdraw if they no longer want to hear from you. This way, you'll be dealing with a more engaged audience, and spam issues won't harm your sender reputation. 


6. Secure your server 

Secure your email account from bots or viruses that can take over your IP address and email URL by implementing suitable security measures and using tools to scan IP addresses.

Check your IP address with an IP lookup tool to see whether anyone else is using it, which could indicate that your internet server has been compromised.

Set up and update email server security measures to avoid malware infestations and the possible eventual blacklisting of your company.


How Email Hippo can help

Your email marketing campaigns, and the reputation of your business may suffer greatly if your recipients or ISP start blocking your emails. Our email verification service can help you protect your sender reputation and steer clear of email blocklists. Start your free trial today.

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Written by: Lisa

Wednesday, 19 January 2022