Newsletter
The State of Cold Email
What is actually landing in the inbox, from a team sending a million cold emails a month. Placement data, provider changes and new research, written by operators. Free.
In each issue
What our placement tests measured
The latest results from the inbox placement log we publish whole, bad months included.
What the providers changed
Google, Microsoft and Yahoo sender rules, and what each change means for a cold email setup.
New studies and playbooks
Research measured on live sending infrastructure, and the operator guides that came out of it.
New free tools
Checkers, planners and MCP tools as they ship, with what each one can and cannot see.
From the Deliverability Hub
Everything we know about getting cold email delivered
3 playbooks
Deliverability Playbooks
Cold email operator strategies we run at Upscale B2B, our own agency, sending a million emails a month. Written from running them, not from reading about them.
See the playbooks3 studies
Deliverability Studies
Original research measured on live sending infrastructure rather than surveyed. Every figure comes from our own fleet or a full sweep of real domains, bad months included.
See the studiesRead now
- Placement · 6 min readEvery placement test we ran on prewarmed inboxesEvery new batch of prewarmed inboxes is seed-tested before it ships, and only stock clearing 95% is deployed. 8 tests, 469,331 messages scored, published whole — a live read on how hard inboxing got through 2026. Every results screen is on the page.
- Domains · 11 min readA study of top-level domains by sends3,415,449 sends split across five TLDs and scored against Google’s permanent domain-reputation verdict. .link drew it 16 times more often than .com, and .org twice as often — and the gap holds inside a single client, where the copy and the list are the same. The TLD you buy predicts this better than anything else we measured, and unlike a blocklist listing it costs replies.
- Blocklists · 10 min readDoes a SURBL listing actually hurt cold email? We tested 2,817 sending domainsA DNS sweep of every live sending domain, not a sample. 43.3% were listed, and reply rate barely moved: 1.14% to 1.16%. Includes the three mechanisms we diagnosed SURBL grouping domains on — shared keyword, redirects to one master, shared nameserver zones — and the fix for each.
- Inboxing · 25 min readThe 2026 Inboxing PlaybookA clean operator guide for building cold email infrastructure that survives longer, routes smarter, and keeps campaigns out of spam.
- Personalization · 12 min readThe Ultimate Liquid Syntax Guide: Hidden Ways To Personalize Cold Emails Using Your SequencerHow to make cold emails feel timely, human, and relevant at scale with Liquid syntax, smarter conditional logic, and better sending context.
- Deliverability · 18 min readHow to Avoid the SPAM Plague in 2026: The Complete List Verification, ESP, ESG & Role Segmentation PlaybookA field-tested cold email segmentation system for cleaner lists, better inbox routing, sharper persona-based copy, and higher reply rates before you ever launch.