Email deliverability: why emails land in spam and how to avoid it
When you send emails from Zeffy, you want them to reach your supporters' inboxes—not their spam folders. This guide explains how email deliverability works at Zeffy and what you can do to improve your results.
How Zeffy handles email deliverability
By default, all emails sent from Zeffy go through Zeffy's sending infrastructure ([email protected]). We manage the domain authentication, sender reputation, and technical deliverability on your behalf.
Zeffy's domain is properly configured with SPF, DKIM, and DMARC authentication records, and we actively monitor sender reputation to ensure emails reach inboxes. You don't need to worry about technical email authentication when using Zeffy's default sending domain.
Sending limits
Without a custom domain: You can send emails to up to 11,000 contacts at once
With a custom domain: You can send emails to up to 30,000 contacts at once
Option 1: Use Zeffy's sending domain (default)
When you send emails without connecting a custom domain, Zeffy handles all deliverability for you:
Emails are sent from [email protected]
Zeffy manages SPF, DKIM, and DMARC authentication
Zeffy monitors sender reputation and handles any deliverability issues
Emails include the sender name you choose, so recipients see your organization's name
This is the easiest option and works well for most organizations. The main limitation is that the "from" email address will be [email protected] rather than your own domain.
Option 2: Connect a custom domain
For stronger brand recognition and improved deliverability, you can connect your organization's own domain to send emails from an address like [email protected].
Benefits of a custom domain
Brand recognition: Recipients see emails coming from your organization's domain, not Zeffy's
Higher sending limits: Send to up to 30,000 contacts at once
Improved deliverability: While Zeffy's default domain is optimized for deliverability, using your own domain can help because email providers recognize emails from your established domain
How to connect a custom domain
See How to customize your email sender domain for step-by-step instructions. You'll need access to your domain's DNS settings to complete the setup.
Common email domains like Gmail, Outlook, and Yahoo cannot be used as custom domains. You must own the domain you want to connect.
Before you send emails
Regardless of which sending option you use, you need to:
Link your bank account: This is a required security measure to prevent Zeffy's email tools from being used for phishing or fraud.
Verify your email address: Confirm that you're authorized to send emails from your account.
See How to validate or verify your email address for instructions.
Content that can affect deliverability
Email providers scan message content for signs of spam. Avoid these common triggers:
Excessive capitalization or exclamation marks
Words like "FREE," "URGENT," or "ACT NOW" in subject lines
Too many links in a single email
Large images with minimal text
Best practices for better results
Send to engaged contacts
Emails perform better when sent to contacts who have recently interacted with your organization. Use lists and segments to target specific audiences.
Clean your contact list regularly
Remove or segment contacts who haven't engaged in a long time. A smaller, engaged list often performs better than a large, inactive one.
Keep subject lines honest
Subject lines should accurately reflect your email content. Misleading subject lines hurt trust and can trigger spam filters.
Let recipients unsubscribe easily
Zeffy automatically includes an unsubscribe link in every email you send. This is required by law and helps maintain good deliverability. When recipients can easily unsubscribe, they're less likely to mark your emails as spam. See How unsubscribes work in Zeffy.
Monitor your results
Check your email performance metrics after sending. Low open rates and high bounce rates can indicate issues. See Track email performance.