Deliverability Rate

What is Deliverability Rate?

Whether you are sending marketing newsletters, transactional emails or keeping in touch with customers, one of the most important metrics for any email campaign is its deliverability rate. Simply put, the deliverability rate refers to the percentage of messages that successfully reach the intended recipient’s inbox. With so many spam filters in place these days, achieving a high deliverability rate takes work. Let’s take a closer look at what email deliverability means.

Delivery rate or inbox placement rate is the folder placement performance metrics of sent mail after being accepted or delivered.

Deliverability is calculated by dividing the number of messages delivered by the total number of messages sent. For example, if you sent out 1,000 emails and 950 were successfully delivered, your deliverability rate would be 95%. The higher the rate, the more effective your email campaign will be at reaching subscribers. Rates below 90% start becoming problematic for communication goals.

There are a few reasons why legitimate emails may be blocked or filtered to spam folders instead of inboxes:

Blacklisted IP Reputation – If an email server has sent spam in the past, its IP address may get blacklisted which can hurt deliverability for all messages from that server.
Poor Email Configuration – Things like incorrect SPF, DKIM or DMARC records can cause deliverability issues if they don’t align with your setup.
Excessive Sending – Sending too many emails too frequently can flag you as a potential spammer. Rate limiting is important.
Low-Quality Content – Messages with little value, questionable links/images or that resemble common spam tend to get filtered more.
Address Hygiene – Invalid or false bounce email addresses in lists hurt deliverability over time.

Monitoring deliverability closely allows problems to be identified and addressed before campaigns are impacted. Services like Email On Acid, Mail-Tester, and MxToolbox provide insight. Some best practices to optimize deliverability include:

Use a reputable transactional email service instead of ISP servers.
Implement authentication protocols like SPF, DKIM and DMARC correctly.
Keep lists clean and confirmed opt-in only. Remove invalid addresses regularly.
Send formatted HTML/plaintext for best rendering across clients.
Limit file sizes of images/attachments and number of external links.
Personalize content by address/name rather than generic mailings.
Gradually ramp up volumes when starting a new list or campaign.
Continuously test mail through third-party validation services.
Request whitelisting by ISPs if deliverability drops significantly.
Monitor spam traps and complaint rates closely to identify issues.

For permission-based marketing emails, earning a high deliverability rate requires an ongoing effort to balance effective communication while avoiding characteristics that could flag messages as spam. Aim for continuous incremental improvements over time through testing, optimization, and list maintenance. This helps ensure more of your legitimate emails reach the intended recipients.

While challenges in deliverability may still occasionally occur outside your control, focusing on the aspects you can improve like sending reputation, list hygiene, content quality, and authentication, will help maximize the number of subscribers receiving your valuable messages in their primary inbox folders as intended. Monitoring rates closely also allows issues to be resolved promptly before significant disruptions to your email campaigns and messaging goals occur.

In summary, deliverability is a critical metric showing the percentage of emails successfully delivered versus how many were sent out. Achieving and maintaining high deliverability requires an active approach through best practices, constant testing and making sure you don’t trigger spam filters. It’s an important factor for effective email marketing over the long run.

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