Learned this the hard way. Sent maybe 50 outreach emails from the same domain handling transactional stuff (signup confirmations, notifications). Domain reputation tanked within a week and the transactional emails users actually needed started landing in spam.
The painful part is recovery. You can fix SPF/DKIM/DMARC in an hour but domain reputation takes weeks to rebuild. Microsoft's SNDS portal shows you almost nothing useful while you wait.
Set up the subdomain split from day one if you're a small SaaS. Costs nothing.
But that would mean that users will have easier time filtering out marketing emails! Which marketing department would want that? /s
Yeah, I wish all marketing email would be clearly flagged as marketing. My bank does this and for them, marketing emails are actually more important than transaction emails, because marketing is creating value for them, and transaction notifications are costing them and only create value for me.
You don't even have to personally, many email providers were blocked by Microsoft for no apparent reason.
We lost critical emails because Microsoft decided one day that alerts from one of our companies was mass spam and started blocking them, after getting their emails daily for 5+ years.
That is one of the ways how Microsoft acts evil. Email was never supposed to be this way. You have zero visibility into why some emails are blocked. One thing is to quarantine emails / put them into spam. But to reject them without any proper technical reason (like wrong SPF) is a nightmare from sysadmin standpoint.
Yep, and no a subdomain does not suddenly insulate your sender reputation.
This BS is pedaled by the email tools who want you to have less friction setting up DNS when onboarding to their tool (less conflicts on a new subdomain).
If you just check the latest version of Google Postmaster Tools, you can see sends from your root domain and subdomain cross-polluting your reputation in Gmail. They aren't dumb.
You've got it - subdomains are sufficient (IIRC). Something like notifications.mycompany.com for the important stuff and news.mycompany.com for the more marketing stuff (and of course someone.else.entirely for the the cold email list "well, surely this one little list couldn't hurt" ... nah, who am I kidding, never use those)
subdomains are not sufficient, unfortunately. I think the instance I'm thinking of is technically web/https (chrome's site safety feature where you can specify a domain as 3rd party content- so when something gets flagged uour entire domain doesn't get blacklisted)- but it's much easier to just grab another domain
The painful part is recovery. You can fix SPF/DKIM/DMARC in an hour but domain reputation takes weeks to rebuild. Microsoft's SNDS portal shows you almost nothing useful while you wait.
Set up the subdomain split from day one if you're a small SaaS. Costs nothing.