Short answer: For an e-commerce password reset, domain reputation is a delivery control. A weak reputation can put the message in spam or get it rejected. Authenticate the domain with SPF, DKIM, and DMARC, remove invalid addresses quickly, and route uncertain failures to the right support queue instead of building an endless resend loop.

The operational constraint changes the provider choice. A one-person SaaS needs the reset message to arrive, but also needs a support workflow for customers who cannot receive it. I would first protect the sending domain and make the failure path explicit. Then I would choose the smallest platform whose monitoring and integration boundaries I can actually operate each week.

What does domain reputation change in a reset flow?

Mailbox providers evaluate domain reputation when assigning spam scores and deciding whether to accept a message. That decision is upstream of the reset screen. If the message is rejected, the customer cannot recover the account.…