How to make sure your email invitations don't go to spam

Nothing reduces event attendance faster than email invitations that never make it past the spam filter.

In 2024, around 10.5% of all marketing emails ended up in the recipient’s spam folder. For event planners who send thousands of email invitations each year, that could mean dozens or even hundreds of guests never see your invites.

Email marketing can be crucial for promoting your events, so ensuring your intended recipients receive your messages is a must. Here’s how to make sure your email doesn’t go to spam and your invitations end up where they belong — in your guests’ inboxes.

How to make sure your email doesn’t go to spam: who decides what is “spam”?

Most email service providers (ESPs) are protected by spam filters that aim to automatically separate most spam.

ESPs use algorithms and filters to do this in several ways:

• Scanning the email’s transmission details for suspicious origins or code
• Checking the sender against known lists of “likely” spammers and phishing scammers
• Scanning of the body of the email for suspicious content

If you are sending legitimate emails, it’s the last point that is most likely to cause your emails to trigger spam filters.

Many of today’s more sophisticated spam filters use natural language processing to decide if an email is spam, while also checking for suspicious links or too many images. They use various criteria to add up the final spam score, which assesses the “spamminess” of your email. If the score hits a certain limit, the filters will mark the email as junk.

This might sound beyond your control when marketing your event, but you have more influence than you think. You can use several tactics to help spam filters understand your emails are legitimate, including:

• Using trusted email marketing platforms
• Scheduling timetables so you don’t send too many emails at once
• Maintaining the proper email authentication protocols
• Personalizing emails for each recipient or audience segment
• Avoiding red flag keywords

Let’s explore how you can use these tactics and more so your event invitations never end up in the spam folder again.

Follow the proper email authentication process 

In 2024, Google, Yahoo, Microsoft, and other email service providers introduced new restrictions for bulk email senders. They define bulk senders as anyone who sends more than 5,000 emails in one day. 

Bulk senders are now required to authenticate themselves, and there are three ways to do so:

• Maintain a Sender Policy Framework (SPF) to prevent domain spoofing
• Create DomainKeys Identified Mail (DKIM) to add digital signatures to email communications
• Adhere to Domain-based Message Authentication, Reporting and Conformance (DMARC) practices so you can specify the actions to take when an email fails authentication

Following these new guidelines can: 

• Improve your sender reputation and domain reputation
• Add you to email whitelists, boosting your IP reputation so inbox providers have more trust in you
• Reduce email deliverability issues 
• Reduce your bounce rate
• Ensure every new email you send gets to the intended recipient

If you haven’t already done so, be sure to set up all DNS settings for SPF, DKIM, and DMARC today.

zkipster maintains SPF, DKIM, and DMARC email authentication protocols for our own domains and subdomains. We also added the BIMI email standard as an additional authentication measure, which means the zkipster brand icon is displayed next to authenticated emails from our domains in recipients’ inboxes. It adds another level of reassurance for recipients and builds on our reputation as a trusted sender.

Learn email marketing basics

Before you plan your next campaign, take a moment to learn more about email marketing basics.

Collect email consent accurately

Whenever you collect an email address — whether that’s through an online form or at an event — try to use a validation strategy like double opt-in.

For example, when someone signs up to your marketing newsletter, a double opt-in means sending them a follow-up email to confirm they do want to sign up for your emails. This indicates they have clearly opted-in twice, which removes almost any possibility of you accidentally emailing “spam traps,” or email addresses specifically created by anti-spam organizations to identify senders who don’t follow proper email practices. 

If you send emails to these trap addresses, it signals to spam filters that you’re not being careful about list building. Since spam traps can’t actually confirm their email addresses (there’s no real person behind them to click the confirmation link), double opt-in works like an extra filter to protect your sender reputation. 

Keep your lists clean 

It’s important to clean your list of people who bounce or mark you as spam. There’s no value in messaging them anyway, and the more emails you send of this sort, the more likely you are to be blacklisted and filtered to spam.

Don’t forget to check for typos, old email addresses, and other contact info inaccuracies that could prevent your emails from reaching the right people. Most email marketing platforms use automation to instantly remove emails from your list if they “hard bounce,” which happens when the recipient’s email address either doesn’t exist or has permanently blocked delivery.

Google now requires you to include an unsubscribe link at the bottom of email content for those who no longer want to receive communications from your email account.

Pick a trusted email marketing platform 

Choose a strong email marketing platform to increase the chances your emails will bypass spam filters. Well-known and trusted platforms effectively enforce compliance with relevant regulations, such as by including automatic “unsubscribe” buttons. When sending mass emails, they also use servers that spam filters know and trust.

Options range from general one-size-fits-all solutions like MailChimp to specialized services like zkipster’s online invitation platform, which is designed for event professionals. 

Verify your email domain 

This is a big one. Our research found that verifying your email-sending domain reliably increases the deliverability of your emails. In short, this is a way to make spam filters trust you more.

Here’s a quick guide on how to use zkipster to do it, and there are similar processes for other professional email tools.

Plan your email campaign

Planning your event email campaign is not as simple as sending blasts to your entire subscriber list. Instead, segment your lists into target audiences and schedule a timetable.

Segment your lists into target audiences 

Avoid sending emails to people who will not be interested in a specific event. This will only irritate them, and it might cause them to mark your messages as spam. A high spam complaint rate can harm your reputation with ESPs and get your messages flagged as spam.

Whether your guests are segmented by location, job title, or other internal criteria (learn about some of the methods Christie’s uses for better segmentation), ensure you only send emails to a tailored and targeted list.

For an easy way to build highly segmented lists, zkipster Audience is a comprehensive contact management solution with advanced filters, segments, tags, and custom fields.

Schedule a timetable 

Sending too many emails can get on people’s nerves. Rather than unsubscribing, they may flag your messages as spam. 

Set a reasonable campaign schedule that builds excitement and intrigues guests without overwhelming their inboxes.

Design your messages strategically 

Bypass your recipients’ spam folders every time with these email campaign best practices. 

From avoiding red flag keywords to personalizing emails, here are some of the many ways to boost your organization’s email deliverability.

Avoid red flag keywords 

Open your own spam folder and you’ll likely notice email subject lines littered with tell-tale spam trigger words. 

Spam filters see certain keywords as suspicious, so keep that in mind when crafting invitations and email communications. Check out this list of 349 email spam trigger words to avoid.   

Go light on images and links

As with certain keywords, spam filters can penalize you for excessive use of images and links. It’s fine to include some images representing your event as long as they’re optimized for the web and you’ve taken rendering for different email clients into account. However, heavy use of images and hyperlinks is a classic trait of spam emails that can make filters highly suspicious of your content.

Personalize emails where you can 

Assuming you have collated a segmented email list, you should be able to use personalized email tags so the recipient’s system sees that it knows their real name. You can even include their name in the email body itself, which notifies spam filters you’re not just guessing who you’re sending it to.

Use recognizable sender information 

Send your messages from a personalized email address. Avoid something like noreply@company.com, which looks generic or automated. Sending a high-volume email campaign from a free Gmail address can also get your messages flagged, since Gmail’s filters prioritize senders who have dedicated, authenticated domain names.

Try to send it from an account associated with a real person and name, or at least something related like events@company.com.

zkipster Events allows for domain whitelabeling, so even though we’re sending the emails on your behalf, your guests won’t see that they’re coming from our email address. Instead, your event emails and invitations will look like they’re coming directly from you.

Track your numbers: open rates and bounced emails

Last but not least, track your campaign for any signs your emails are being perceived as spam. There’s no way around this step — you need to analyze your metrics and know your engagement rates if you want to optimize your email campaigns and improve the deliverability of your event invitations.

Monitor email open rates 

Keep an eye on open and click rates. If you notice a trend where guests are increasingly ignoring your emails, it suggests they may be getting fatigued. Several unopened emails can convince spam filters your messages are of lower quality.

That may not be an issue with the particular person you’re emailing (after all, they’re not opening your emails anyway), but it can create a bigger problem if a company network decides your emails are spam. If that happens, other people at the company will also start receiving your messages in their spam folder.

Check for bounced emails 

Many professional email tools include some kind of spam and bounce tracking. Those metrics can help you spot issues before they become serious trends, and pinpoint if certain bounces are happening because of spam filters or inaccurate contact info.

There are several reasons why emails bounce. Check out this article to learn what to do when emails are dropped, designated undeliverable, blocked, or when the recipient can’t be found.

Monitor your inbox placement rate (IPR)

Finally, don’t overlook your inbox placement rate (IPR). Unlike basic delivery confirmation, which only tells you an email reached the recipient’s email server, IPR reveals where those emails actually land: the recipient’s inbox, spam folder, or promotions tab. 

An email can be successfully delivered, but it may still perform poorly if most messages end up in spam. In other words, your IPR directly impacts whether recipients will actually see and open your invitations. Many ESPs offer IPR tracking tools, or you can use third-party services to monitor where your emails are landing across different email clients. 

If you notice your IPR dropping, it’s time to review your sender reputation, email content, and authentication settings before your next campaign.

Don’t let your event marketing campaign fail before it starts 

It takes some effort to get guests to not only open your emails, but to also act on your messages and RSVP to your events. 

Give yourself the best odds possible so the next time you email clients and guests, your messages land directly in their inbox rather than their junk folder.