SMTP RElay with DKIM and DMARC of Office 365

Super Contributor

We have mail sending apps that uses SMTP relay.


if we are going to deploy DKIM and DMARC , how can we include the mails being sent by mail sending apps in DKIM/DMARC protection?

1 Reply

@Marvin Oco This is something we work with a lot for out customers. It’s quite straight forward. Let’s take Mailchimp as an example. With Exchange Online you most likely have create an SPF record already. Then you set up DKIM for Office 365.


For DKIM you create a CNAME record for with this value:
For SPF you add this TXT value:
See the links below.


As a general statement: The best idea is to use subdomains for your marketing needs, for instance send those mails from marketing.<yourdomain>.com.


Please come back with questions, and I’ll guide you through this jungle. Personally, I always recommend in order to work with DMARC.
MailChimp and DMARC: How to Make it Work!


Best regards, Jon Alfred Smith, Senior Consultant at Lillevik IT