Email Authentication: The Complete Guide for Shopify Stores

What is Email Authentication?

Email authentication is a set of technologies that verify an email really came from who it claims to come from. It’s like checking ID before allowing someone to speak on behalf of your business.

Without email authentication, anyone can send emails that appear to come from your Shopify store—even criminals trying to scam your customers.

The Three Pillars of Email Authentication

SPF (Sender Policy Framework)

Answers: “Did this email come from an authorized server?”

SPF lets you publish a list of servers allowed to send email from your domain. When an email arrives, the receiving server checks if the sending server is on your approved list.

DKIM (DomainKeys Identified Mail)

Answers: “Is this email genuine and unmodified?”

DKIM adds a cryptographic signature to every email. The receiving server uses your published public key to verify the signature, proving the email is authentic.

DMARC (Domain-based Message Authentication)

Answers: “What should I do if SPF or DKIM fails?”

DMARC ties SPF and DKIM together with a policy. It tells receiving servers whether to deliver, quarantine, or reject emails that fail authentication—and sends you reports about authentication results.

Why Shopify Merchants Need Email Authentication

Protect Your Customers

Scammers regularly impersonate Shopify stores to steal customer payment information. Email authentication helps receiving servers identify and block these fake emails.

Improve Deliverability

Email providers like Gmail and Outlook prioritize authenticated email. Without proper authentication, even your legitimate emails may land in spam.

Meet Industry Requirements

Google and Yahoo now require email authentication for bulk senders. If you send marketing emails, you likely need this.

Protect Your Reputation

When scammers send emails from your domain, some recipients will blame you. Proper authentication protects your brand.

How These Work Together

Imagine you’re mailing a package:

1. SPF is like the return address. It shows the package came from your authorized shipping location.

2. DKIM is like a tamper-evident seal. It proves the package wasn’t opened or modified in transit.

3. DMARC is like your instructions to the recipient: “If the return address is wrong or the seal is broken, refuse the package and tell me about it.”

All three work together to create a complete authentication system.

Checking Your Email Authentication

Quick Check Tools

• MXToolbox (mxtoolbox.com/SuperTool.aspx)
• Google Admin Toolbox (toolbox.googleapps.com/apps/checkmx/)
• Mail-tester (mail-tester.com)

What to Look For

SPF: Look for a TXT record starting with v=spf1

v=spf1 include:shops.shopify.com include:_spf.google.com -all

DKIM: Look for a TXT record at a selector subdomain

selector._domainkey.yourstore.com

DMARC: Look for a TXT record at _dmarc

v=DMARC1; p=quarantine; rua=mailto:dmarc@yourstore.com

Setting Up Email Authentication

Step 1: Inventory Your Email Services

List everything that sends email from your domain:

• Shopify order notifications
• Email marketing (Klaviyo, Mailchimp, etc.)
• Business email (Google Workspace, Microsoft 365)
• Support systems (Zendesk, Help Scout, etc.)

Step 2: Configure SPF

Create an SPF record that includes all your legitimate sending services:

v=spf1 include:shops.shopify.com include:sendgrid.net include:_spf.google.com -all

Step 3: Configure DKIM

Set up DKIM for each email service. Each provider has their own process—check their documentation.

Step 4: Implement DMARC

Start with monitoring mode:

v=DMARC1; p=none; rua=mailto:dmarc-reports@yourstore.com

Step 5: Monitor and Strengthen

Review DMARC reports, fix any issues, then gradually strengthen your policy to quarantine and eventually reject.

Common Authentication Mistakes

Incomplete SPF

Forgetting to include a sending service means its emails fail SPF. Audit all your email senders.

Too Many SPF Lookups

SPF allows only 10 DNS lookups. Too many includes break SPF entirely.

Missing DKIM for New Services

Adding a new email tool without configuring DKIM causes authentication failures.

Jumping to DMARC Reject

Starting DMARC at reject without monitoring first can block legitimate email.

How Recon Helps

Recon monitors your email authentication by:

• Verifying SPF, DKIM, and DMARC are properly configured
• Alerting you if authentication records are missing or broken
• Checking that all sending services are authorized
• Providing guidance to fix authentication issues

FAQ

Q: Will email authentication affect my Shopify order emails?

A: If configured correctly, authentication improves delivery of order emails. Shopify’s servers are designed to work with proper email authentication.

Q: How long does it take to set up email authentication?

A: Basic SPF setup takes minutes. Full implementation of SPF, DKIM, and DMARC with proper testing typically takes 2-4 weeks.

Q: Do I need all three (SPF, DKIM, DMARC)?

A: For complete protection, yes. SPF and DKIM each solve different problems, and DMARC enforces both. Start with SPF, add DKIM, then implement DMARC.