The Fastest Path to Yahoo Inboxes: Analyzing SMTP Providers for Optimal Delivery
The Warmy Research Team conducted an experiment to uncover which among different SMTP providers result in a faster delivery to Yahoo inboxes.
Don’t Let Your Pixels Hide: The Impact of Tracking Links and Images on Gmail and Google Workspace Deliverability
In cold email outreach campaigns, deliverability is a legit concern. And even after you draft the perfect email, the success of your campaign hinges on the email getting into the recipient’s inbox. But even if an email does make it to the inbox, there’s another challenge: tracking accuracy. For Gmail and Google Workspace (GW) users, […]
Signature Showdown: Crafting the Perfect Email Signature for Maximum Deliverability
In a world where email marketers compete for open rates, click-through rates, and conversions, the email signature may easily be overlooked. Or it may even be a last-minute addition. However, did you know it could actually be the difference between your email landing in the inbox or getting lost in the spam folder? The battle […]
Cracking the Inbox Code: What Speeds Up Outlook Delivery from Different SMTP Providers?
If you’ve ever wondered why some domains warm up faster than others, you’re not alone. For marketers and businesses, speed to inbox can make or break a campaign’s success—especially when sending to major providers like Outlook. With more than 400 million active email users worldwide and an 8.10% market share, getting your emails to land […]
It’s Time to Bounce Back: ESP-Specific Strategies That Actually Work
Whether you are running cold outreach, nurturing leads, or sending out transactional updates, bounced emails are an annoyance—and more than that, they signal that something is wrong. At Warmy.io, we’ve been running controlled deliverability experiments across major email service providers (ESPs)—Gmail, Outlook/MS365, Yahoo, AOL, and Zoho—to understand exactly why emails bounce, what those bounce codes […]
Thread or Dread: GSuite vs. MS365 in Follow-Up Deliverability
In the world of email deliverability, most senders obsess over one moment: the first send. Will it land in the inbox or spiral into spam? But what if that moment matters far more than we ever realized? At Warmy.io, we set out to explore a critical but overlooked question: Does the inbox placement of your […]
Mastering Global Email Deliverability in 2024–2025
In today’s interconnected world, email as a communication channel is a double-edged sword. It’s easy, quick and allows businesses to connect with multiple clients at the same time. But some specific sending behavior combined with other technical factors can lead businesses to be labeled as questionable–not a great result for a worldwide business. Thus, worldwide email […]
Are Blacklists Killing Your Emails? A Deep Dive into How They Influence Email Providers
In 2025, email remains one of the best ways to reach prospects and customers. But deliverability isn’t guaranteed—especially if your domain or IP lands on a third-party spam blacklist. These DNS-based blocklists (DNSBLs) are maintained by anti-spam organizations and used by email providers to filter out unwanted messages. For senders, being listed in even one […]
How to Avoid Email Blocks: Lessons from MS365’s Deliverability Research
Email deliverability—crucial yet often elusive goal for businesses aiming to connect with their audience. But there’s a harsh reality: As good as your content is and as personalized as your outreach is, if your emails don’t reach that inbox, they just don’t work. In a time when inboxes are bombarded with spam and unwanted emails, […]
The Email Deliverability Playbook: 5 Key Trends That Will Define Inbox Success in 2025
Welcome to the new email landscape where email deliverability has never been more important—or more complex. With inbox providers tightening their rules, AI-driven filters evolving fast, and new privacy laws rolling out across the globe, what worked last year simply won’t cut it in 2025. The Warmy.io Research Team created this guide: to give Warmy […]
