Constant Contact Email Authentication Setup

Email marketing platform for small businesses and nonprofits. This guide covers the complete email authentication stack for Constant Contact: SPF, DKIM, and DMARC. Each section gives you the exact DNS records, step-by-step instructions, common pitfalls, and how to verify your setup.

Jump to a Protocol

SPF

Authorize which servers can send email for your domain.

DKIM

Cryptographically sign your outgoing email so receivers can verify it.

DMARC

Tell receivers what to do when SPF or DKIM fail.

SPFTest with our SPF Checker →

How to Set Up SPF for Constant Contact

Authorize Constant Contact to send marketing email on behalf of your domain by adding the correct SPF include.

Quick Answer — The Record You Need

Type

TXT

Host / Name

Value

v=spf1 include:spf.constantcontact.com ~all

Add include:spf.constantcontact.com to your existing SPF record.

Step-by-Step Setup

Log in to Constant Contact

Go to app.constantcontact.com and sign in.

Navigate to self-authentication

Go to Account Settings > Self-Authentication. This is where you manage domain authentication.

Check your existing SPF record

Look up your current SPF record.

dig TXT yourdomain.com +short | grep spf

Add Constant Contact to your SPF record

Add include:spf.constantcontact.com to your existing SPF record.

v=spf1 include:spf.constantcontact.com ~all

Verify in Constant Contact

Return to Self-Authentication settings and verify the domain.

Before & After

Before

v=spf1 include:_spf.google.com ~all

After

v=spf1 include:_spf.google.com include:spf.constantcontact.com ~all

SPF Gotchas

The include is spf.constantcontact.com, not constantcontact.com.
Constant Contact calls their domain setup process "self-authentication" in the account settings.
If you are on a legacy Constant Contact plan, the authentication options may be in a different location. Check under My Account.

SPF FAQ

What SPF record do I need for Constant Contact?

Add include:spf.constantcontact.com to your SPF record.

What is Constant Contact self-authentication?

Self-authentication is Constant Contact's domain verification process. It involves adding DNS records to prove you own the domain and authorize Constant Contact to send on its behalf.

Is SPF enough for Constant Contact authentication?

Constant Contact recommends setting up both SPF and DKIM (via CNAME records) for complete authentication.

DKIMTest with our DKIM Checker →

How to Set Up DKIM for Constant Contact

Enable DKIM for Constant Contact by publishing CNAME records that allow Constant Contact to sign your marketing email.

Quick Answer — The Record You Need

Type

CNAME

Host / Name

ctct1._domainkey

Value

ctct1.domainkey.constantcontact.com

Constant Contact provides two CNAME records (ctct1 and ctct2) during self-authentication.

Step-by-Step Setup

Log in to Constant Contact

Go to app.constantcontact.com and sign in.

Go to self-authentication

Navigate to Account Settings > Self-Authentication.

Get the DKIM records

Constant Contact displays the CNAME records needed for DKIM.

Add the CNAME records to DNS

Create the CNAME records in your DNS provider.

ctct1._domainkey.yourdomain.com  CNAME  ctct1.domainkey.constantcontact.com
ctct2._domainkey.yourdomain.com  CNAME  ctct2.domainkey.constantcontact.com

Verify in Constant Contact

Click "Verify" in the self-authentication settings. Once DNS propagates, DKIM will activate.

DKIM Gotchas

Constant Contact uses CNAME records for DKIM with selectors ctct1 and ctct2.
Both CNAME records must be added for complete DKIM configuration.
Self-authentication in Constant Contact handles both SPF and DKIM together. Complete the full process for best results.

DKIM FAQ

What DKIM selectors does Constant Contact use?

Constant Contact uses ctct1 and ctct2 as DKIM selectors, published as CNAME records.

Does Constant Contact rotate DKIM keys?

Yes. Since DKIM records are CNAMEs pointing to Constant Contact-managed DNS, they can rotate keys without requiring your DNS changes.

Is DKIM required for Constant Contact?

Strongly recommended. DKIM improves deliverability and is needed for DMARC alignment.

DMARCTest with our DMARC Checker →

How to Set Up DMARC for Constant Contact

Publish a DMARC record to protect your domain when sending marketing email through Constant Contact.

Quick Answer — The Record You Need

Type

TXT

Host / Name

_dmarc

Value

v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1

Complete Constant Contact self-authentication before enforcing DMARC.

Step-by-Step Setup

Complete self-authentication

Finish the Constant Contact self-authentication process (SPF + DKIM).

Test email authentication

Send a test campaign and verify SPF and DKIM pass in the email headers.

Create the DMARC record

Add a TXT record at _dmarc.yourdomain.com.

v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1

Monitor reports

Review DMARC reports for 2-4 weeks.

Enforce gradually

Move from p=none to p=quarantine to p=reject.

DMARC Gotchas

Constant Contact emails will fail DMARC alignment if self-authentication is not complete.
Ensure all email services sending from your domain are authenticated before enforcing DMARC.
Constant Contact sends email from shared IPs. DKIM alignment (not SPF) is the primary DMARC alignment mechanism.

DMARC FAQ

Does Constant Contact support DMARC?

Yes. With self-authentication complete, Constant Contact emails pass DKIM alignment for DMARC.

Will DMARC enforcement block Constant Contact emails?

Only if self-authentication is not set up. With SPF and DKIM configured, emails pass DMARC.

Do I need DMARC for Constant Contact?

DMARC is strongly recommended. Google and Yahoo require DMARC for bulk senders.

Verify Your Constant Contact Setup

Once your SPF, DKIM, and DMARC records are in place, run a full domain scan to confirm everything is configured correctly. DNS changes typically propagate within minutes but can take up to 48 hours.

Setup Guides for Other Providers

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