When you send an email, Google or Microsoft doesn't just deliver it. They score it. Every email that leaves your mailbox contributes to a running assessment of your domain's sending behaviour. That score determines whether your next email lands in primary, promotions, spam — or gets blocked entirely.
What inbox providers are looking at
Google and Microsoft evaluate your domain based on several signals, updated continuously as you send:
Domain reputation. The score attached to your sending domain — not just your email address. If one mailbox on a domain damages the score, all mailboxes on that domain are affected.
Send volume and consistency. Mailboxes that suddenly send large volumes look suspicious. Steady, gradually increasing volume looks like a normal person.
Bounce rate. Emails sent to addresses that no longer exist bounce back. A high bounce rate is a strong signal that you are sending to unverified lists — a red flag for spam.
Engagement rate. Do people reply to your emails? Do they open them without immediately deleting? Positive engagement improves your score. Being marked as spam destroys it.
Authentication. SPF, DKIM, and DMARC records tell receiving servers that your domain is who it says it is. Missing these is an automatic trust deduction.
Domain score, not mailbox score
This is one of the most commonly misunderstood points. Your sending reputation lives at the domain level — not the individual email address level.
This means: if you have three mailboxes on getreplies.io and one of them is misconfigured and starts producing bounces, all three mailboxes suffer. It also means you should never run outreach from your primary business domain.
The inbox placement hierarchy
Inbox providers route incoming email to one of four places, in roughly this order of desirability:
Primary inbox. The sender is trusted, the email looks personal and relevant. This is where your emails need to land.
Promotions tab (Gmail). Often triggered by tracking pixels, unsubscribe links, and marketing-style formatting. Not ideal for cold outreach.
Spam / junk. The email is flagged as bulk or unsolicited. Effectively invisible to the recipient.
Blocked / rejected. The receiving server refuses the email entirely. Usually happens when the sending domain is blacklisted.
GetReplies is specifically designed to keep your emails in the primary inbox. The features described in the rest of this section — continuous warmup, dynamic ramp-up, reply optimisation, and bot filtering — all serve this single goal.