You designed a beautiful invitation for your event, fine-tuned its subject line, segmented your contact list, and clicked "send". Mission accomplished? Not quite.
According to a 2022 study by Campaign Monitor, the average open rate is around 21.5%. But between sending an email and actually receiving it lies a factor that's often overlooked: deliverability.
It's one of the most powerful and underrated levers of marketing performance.
In this article, we explain what deliverability is, what factors influence it, and above all, how to improve it in practice.
Definition of email deliverability
Deliverability refers to your email's ability to reach the recipient's inbox without being blocked by spam filters or rejected by servers.
Contrary to popular belief, clicking "send" doesn't mean the email has been received.
How is it calculated?
You can measure deliverability using a simple indicator: the deliverability rate. It's calculated as follows:
Deliverability rate = (Number of emails delivered / Number of emails sent) x 100
For example, if you send 300 invitations and 288 reach their destination, your deliverability rate is 96%. A good rate is generally considered to be above 95%.
Difference with the open rate
You need to clearly distinguish between the deliverability rate and the open rate.
The deliverability rate shows whether the email reached the inbox, while the open rate shows whether the recipient opened the email.
Keep in mind that you can't have a good open rate without first having good deliverability: it's the first condition for an effective email.
Sending statuses you should know
An invitation sending platform like Digitevent provides detailed sending statuses that help you understand what happens after you click "Send":
- Sending in progress: the message is on its way. It has left the platform but hasn't yet been accepted by the recipient's server.
- Sent: the email has been accepted by the receiving server. It can now appear in the inbox, or in spam.
- Delayed: the recipient's server is temporarily unavailable. Sending will be retried for 72 hours.
- Opened / Clicked: the email was viewed or a link was clicked. These are interaction signs that confirm the message was indeed delivered.
- Dropped: the email wasn't sent because the address is known to be invalid.
- Hard bounce: the email was rejected because the recipient's address is incorrect or no longer exists.
A high proportion of bounces or drops can, for example, explain a drop in your deliverability rate.
Keep in mind that analyzing the sending statuses of your invitations is essential for assessing the quality of your contact list.
💬 Quote from the Digitevent expert:
"Deliverability is the passport for your emails: without the right technical stamps and a solid reputation, your messages will never make it to the inbox." - Damien Remise, Account Manager at Digitevent
What factors influence email deliverability?
Deliverability doesn't depend on a single factor, but on a combination of technical, behavioral, and contextual factors. Here are the 4 main ones:
Sender reputation: your reputation is directly influenced by your sending practices. Every time you send an email, mail servers evaluate your behavior using several criteria:
- The complaint rate: how many recipients mark your emails as spam?
- The bounce rate: how many emails are returned due to invalid addresses?
- The engagement rate: are your emails opened, clicked, or deleted without being read?
Message content: tone, keywords, and formatting can trigger spam filters.
Technical configuration: to be properly identified as a trusted sender, your IT department must configure three key protocols that act as the digital identity documents of your emails and play a central role in their credibility:
- SPF (Sender Policy Framework), which verifies that the email was indeed sent from a server authorized by your domain.
- DKIM (DomainKeys Identified Mail), which adds a digital signature guaranteeing that the message hasn't been altered.
- DMARC, which orchestrates these two protocols and tells receiving servers what to do if authentication fails (let it through, quarantine it, or reject it).
Sending volume and frequency: sudden spikes or an excessive pace can be seen as suspicious.
Many factors affect your invitations' ability to reach their target. Fortunately, a few simple and concrete rules can help you significantly improve your deliverability rate.
8 best practices to improve the deliverability of your invitations
Understanding the factors behind email deliverability is good. Putting them into practice is better. Here are some simple and effective actions to boost the performance of your campaigns.
1. Regularly clean your contact list
Don't forget that a clean list is essential for maintaining a good sender reputation. Inactive, incorrect, or outdated addresses lead to sending errors or automatic drops.
To keep an effective contact list:
- Check or remove contacts that have been inactive for more than 6 months.
- Avoid purchased lists, or use trusted providers.
- Use email address validation tools.
A high bounce rate is often a sign of an unqualified contact list. Over time, this can seriously damage your sender reputation, or even cause your domain name to be systematically flagged as spam.
Don't hesitate to use online tools like Kickbox to test the quality of your database.
2. Correctly identify your domain
Email providers like Gmail or Outlook check whether your invitations are actually sent by you. Reach out to your IT department to make sure your domain name is properly authenticated and that the SPF, DKIM, and DMARC protocols are correctly configured.
If most recipients belong to the same organization, involve that organization's IT department so they can recognize a specific IP address: this is whitelisting. This practice involves adding a sender or IP to a trusted list, to prevent emails from being blocked.
Finally, make sure your sending address is consistent and professional.
3. Pay attention to the content of your invitations
The tone, style, and structure of your email directly influence whether it lands in the inbox, or in spam.
Spam filters analyze both the substance and the form of your emails:
- Avoid overly commercial phrasing, the well-known "spam words": "Free !!!", Refunded, Gift, 100% Free, No fees, You've won!, etc.
- Limit capital letters and exclamation marks.
- Watch the balance between images and text in your invitations.
- Write content that's readable even without images.
- Add personalization elements (first name, company, etc.).
4. Keep a good sending pace
If you send too many emails at once or too frequently, you can trigger alerts from email providers. That's why you should:
- Split your sends to avoid traffic spikes.
- Adopt a consistent frequency suited to your audience.
- Avoid sending to thousands of recipients all at once.
Some servers delay or refuse sends deemed "sudden" or too large. Note that a good email sending platform includes these practices by default in its features.
5. Always offer a simple unsubscribe option
Under the General Data Protection Regulation (GDPR), an unsubscribe link is mandatory.
Don't forget to place a visible link in the footer, and don't complicate the process (no multiple clicks, no proof required).
A user who can't unsubscribe easily is more likely to report your email as spam.
Guaranteeing an easy unsubscribe process builds trust, and is therefore beneficial for your reputation.
6. Test your emails
A well-written email can still end up in spam if it isn't tested properly.
Each email service can interpret your email differently.
- Send an email deliverability test to several providers (Gmail, Outlook, Yahoo, etc.).
- Analyze the layout, readability, and inbox placement, whether on desktop or mobile, to ensure an optimal experience on any device.
No need to worry: there are tools like Mail-tester to test the deliverability of your emails.
7. Analyze the results and adjust
Statistics are your best allies for understanding and fixing what's not working. Keep an eye on these metrics:
- Sending statuses (sent, in progress, delayed, etc.).
- The deliverability rate (Number of emails delivered / Number of emails sent) x 100
- The bounce rate (Number of emails not delivered / Number of emails sent) × 100.
- The open rate (Number of emails opened / Number of emails delivered) × 100.
- The click rate (Number of clicks on a link / Number of emails delivered) × 100.
- Unsubscribes and spam complaints.
Quickly spotting anomalies lets you react before they affect your future campaigns.
8. Use a reliable sending platform
The solution you use to send your invitations plays an essential role in their deliverability. Not all platforms are equal: some apply strict rules to avoid blocks, others don't.
Choose a reliable invitation sending platform like Digitevent, which includes technical best practices by default and lets you clearly analyze your campaign statistics.
As you can see, deliverability isn't just a technical matter: it's a genuine performance lever for your events. An invitation that isn't delivered is a message that will never be read, one less attendee, and a missed opportunity.
Don't let your invitations fall through the cracks. Try Digitevent now to make sure your emails reach their targets, effortlessly.
