How to properly warm up a cold email inbox in 2026. Full process breakdown
noobsender · 2026-02-15 · 1,840 views
Just bought 20 new inboxes and want to make sure I warm them up correctly. Last time I rushed warmup and got 3 accounts suspended within a week. Here is what I have learned since then.
Week 1: Enable warmup tool (I use Instantly's built-in warmup). Start at 5-10 warmup emails per day. Do NOT send any cold emails yet. Let the inbox build a sending history with positive engagement signals (opens, replies, moves to inbox).
Week 2: Ramp warmup to 20-30 emails per day. Still no cold sends. Monitor inbox placement via GlockApps. You want 90%+ inbox placement before moving forward.
Week 3: Start sending cold emails at 5 per day per inbox. Keep warmup running alongside. Monitor bounce rate and spam complaints daily.
Week 4: If metrics look good (reply rate above 2%, bounce under 2%, no spam complaints), ramp to 10-15 cold emails per day. Keep warmup running at a reduced volume.
Ongoing: Never turn off warmup completely. Keep it running at 10-15 per day even after fully ramped. This maintains positive engagement signals that protect your sender reputation.
The biggest mistake people make is trying to skip from 0 to 20 cold emails per day in the first week. Google and Microsoft track sending patterns and sudden spikes trigger suspensions. Patience during warmup saves you money and headaches long term.
Comments (5)
bouncebetty · 2026-02-16
This is a solid warmup guide. One thing I would add — check your inbox placement with GlockApps or mail-tester.com at the end of week 2 before you start cold sending. If you are not at 90%+ inbox placement, keep warming up. Do not rush it. I have seen too many people start sending after 10 days and tank their reputation immediately.
coldkingdom · 2026-02-16
the week 1 to week 4 timeline is accurate. tried to shortcut this once and went from 0 to 20/day in 5 days. got 3 accounts suspended within a week. patience during warmup literally saves you money
noobsender · 2026-02-17
quick question — do you keep warmup running even after you're fully ramped up on cold sends? or do you turn it off once you're at 20/day?
warmup_wiz · MailReach · 2026-02-18
@noobsender Never turn off warmup completely. Keep it running at 10-15/day even when fully ramped. The positive engagement signals from warmup emails protect your sender reputation and counterbalance any negative signals from cold sends. Think of warmup as ongoing maintenance, not a one-time setup.
techsales22 · 2026-02-19
ngl i skipped the testing step (day 21 GlockApps check) and it cost me. was sending into spam for 3 days before i even noticed. always test before launching your first campaign