How to check and improve your email domain health

What is email domain health?

Email domain health refers to how well your sending domain is configured for reliable email delivery. A healthy domain has valid MX records, a properly configured SPF record, a DMARC policy, and a clean blacklist status. Gaps in any of these four areas can cause emails to land in spam or be rejected entirely.

The four pillars of email domain health

MX records tell the internet which mail servers are responsible for receiving email at your domain. Without valid MX records, you cannot receive email and your domain will appear inactive to validation tools — which is a signal that emails sent to addresses at that domain will bounce.

SPF (Sender Policy Framework) declares which servers and IP addresses are authorised to send email on behalf of your domain. A missing or misconfigured SPF record means receiving servers cannot verify the origin of your emails, making them more likely to be flagged as spam.

DMARC (Domain-based Message Authentication, Reporting and Conformance) defines what happens when an email fails SPF or DKIM authentication. Without DMARC, there is no policy — emails that fail authentication are delivered or rejected at the discretion of the receiving server, with no consistency or reporting.

Blacklist status refers to whether your sending domain or IP address appears on any of the major email blacklists maintained by organisations like Spamhaus, Barracuda, or SURBL. A blacklisted domain causes emails to be routed to spam or blocked at the server level by any provider that references those lists.

How to run a health check

Use the BounceProtect Email Health Checker to run all four checks on any domain in seconds. The tool returns a health score out of 100 and a plain-English summary of each check with specific action items for anything that fails.

Common issues and how to fix them

Missing SPF record — Add a TXT record to your DNS with the value v=spf1 include:[your-provider] ~all. Use the BounceProtect SPF Generator to build the correct record for your email providers.

SPF too permissive — A record ending in +all means any server in the world can send email from your domain. Change this to ~all or -all immediately.

DMARC at p=none — A DMARC record with p=none provides no protection. Review your DMARC reports and move to p=quarantine once you understand your email flow.

Blacklist hit — If your domain appears on a blacklist, identify the cause first (spam complaints, compromised account, poor list hygiene). Then submit a delisting request to each blacklist. BounceProtect monitors blacklist status automatically so you are alerted before it affects a campaign.

How often to check domain health

Check after any major infrastructure change (new email provider, new IP address, new sending domain). For active sending domains, monthly checks are a reasonable baseline. BounceProtect monitors blacklist status continuously and alerts you automatically.