We analyzed 21,297 cold email replies across every major email provider. It revealed some surprising patterns about Google vs Outlook vs others. Here's everything we learned:
First, here's how we ran the analysis: - Exported one week of replies from Airtable - Used Google's DNS endpoint in Clay to identify each recipient's email provider - Categorized replies as Interested, Not Interested, or Automated.
Dataset breakdown: - 21,297 total replies analyzed - 4,086 real replies (Interested + Not Interested) - 16,433 automated replies (OOO/NOU) - Outlook share: 10.7% of all replies
Finding #1: Outlook underperforms in volume but isn't dead. Outlook represented just 10.7% of all replies. Lower than Google and SMTP, but still thousands of conversations. Clearly harder to penetrate, but not impossible.
Finding #2: 77% of all replies were automated. Most were OOO or "no longer at the company" responses. These inflate response rates without creating pipeline. If 15-20% are "no longer at company," you're hurting deliverability with unnecessary sends.
Practical takeaways: Prioritize Google first, then SMTP, then Outlook when sending. Filter aggressively for NOU/OOO replies. Test ultra-short copy for Outlook. Preserve domain health by cutting noise and focusing on right providers.
@NickAbraham12 Best cold email for hitting the outlook inbox right now is simply: “Are you the best person at {company name} to speak with about {relevant business priority}?” There’s no other way.
@NickAbraham12 Love this analysis! We actually help users test both Google & Outlook setups through EmailAstra — all domains pre-warmed and verified for max deliverability