SPF - Sender Policy Framework

For email authentication: optimize your deliverability with a digital signature
Sender Policy Framework CleverReach

Improve email delivery rate with SPF

Less spam
SPF signature is used for email authentication and helps protect your newsletters from spam.

Authenticate as a legitimate sender
Mail servers participating in the SPF process recognize your electronic signature and can thus identify you as a verified sender.

Enhance reputation
By setting an SPF entry, you increase your reputation as a sender.

What is an SPF signature?

The sender ID (also: Sender ID Framework) and SPF (Sender Policy Framework) are digital signatures for clearly identifying the sender of a mailing. The most commonly used one is SPF.

  • The signature confirms the sender’s authenticity
  • Email servers can see from the SPF record if email address and sender correspond and therefore only deliver the right emails.

Get started now with CleverReach!

Specialized in target group-oriented marketing campaigns, our email marketing software effectively supports you in the successful implementation of email marketing campaigns. Manage up to 250 recipients and send up to 1,000 emails per month free of charge!

1. The significance of SPF and email authentication

Sender Policy Framework Significance CleverReach
  • Most providers and spam filters work with so-called SPF queries
  • These queries help to identify if the sending server has the permission to send emails with your reply-to-address. The email has to be sent from a server that is part of the Resource Record of the DNS of the sending domain.
  • This indicates the receiving mail program that your email comes from an authenticated domain and is not spam mail.

Place a DNS record in your domain to use SPF. The Resource Record shows which IP addresses may send emails for your domain.

  • For CleverReach to recognize the sending server as an authorized server, the respective record must be there.

2. Place an SPF record for your mailings

Sender Policy Framework Place an SPF CleverReach
  • TXT record for new SPF record
    In case you don’t have an established SPF record yet, place this TXT record for the respective sending domain for your provider:v=spf1 a mx include:spf.crsend.com ~all
  • TXT record for existing SPF record:
    If you already have an SPF record, don’t overwrite it, but just add the CleverReach® part include:spf.crsend.com to it. In our exemplary record, it would look like this:v=spf1 include:spf.example.com include:spf.crsend.com ~all
  • You can use your own domain as a return address

3. What do you need authentication signatures for?

Sender Policy Framework Authentication Signatures CleverReach
  • Signatures for email authentication were developed to minimize the quantity of spam mails.
  • SPF prevents email forging. Spammers use this technique to hide where their spam mails come from. Providers work against these spammers with different methods of email certification to protect their customers from unwanted spam.
  • Senders with an SPF record can be sure they are recognized as serious senders. Emails go directly to your subscribers’ inboxes and don’t end up in their spam folders.

4. SPF records: your unique digital signature

Sender Policy Framework SPF Records CleverReach
  • SPF records improve your reputation as a sender
  • Mail servers using SPF recognize your electronic signature and identify you as a verified real sender. This minimizes the possibility that you are marked as spam, plus it improves your delivery rate.


  • The switch can last up to 24 hours.
  • Not all providers support SPF.

5. Get started for free with CleverReach!

CleverReach Newsletter Tool kostenlos testen


  • up to 2,500 recipients
  • and send up to 10,000 emails per month for free!

Our Lite Plan has no limited running-term. There is no setup fee and no contractual obligations.

For more emails and features, choose between our Flex, Essential or Enterprise plans. Our price plan calculator will tell you which plan is the best for you!