The Complete Guide to Cold Email

Everything I've learned about cold email—deliverability, verification, writing, and follow-ups. No fluff, just what actually works.

Cold email Email outreach Deliverability Pillar post
Quinten Kamphuis avatar
Quinten Kamphuis Founder & CEO
9 min read

Everything I’ve learned about cold email—deliverability, verification, writing, and follow-ups. No fluff, just what actually works.

1. Domain & Infrastructure Setup

Your domain setup can make or break your cold email game. I’ve burned domains, gotten blacklisted, and learned every lesson the hard way. Now I set up infrastructure properly from day one—and my deliverability shows it.

Domain Setup & Authentication

SPF, DKIM, DMARC—sounds like alphabet soup but this stuff is non-negotiable. Without proper authentication, email providers don’t trust you. I set this up for every domain before sending a single email. Skip it and you’re asking for the spam folder.

📌 Start here: SPF DKIM DMARC setup for cold email senders (Full Guide 2026)

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Domain Reputation & Health

Your domain reputation follows you everywhere. Once it’s trashed, recovery takes weeks or months. I monitor my domains obsessively now because I’ve seen what happens when you don’t. These guides help you protect what you’ve built.

📌 Start here: Domain reputation cold email protection tips (Expert Advice)

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Domain Rotation & Scaling

Sending high volume from one domain is a recipe for disaster. I learned to rotate domains and spread the load so no single domain gets hammered. It’s how agencies scale without burning everything down.

📌 Start here: Domain rotation automation for safe outreach scaling (How-To 2026)

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2. Email Warmup & Inbox Placement

New domains and inboxes need warmup before you can send at scale. Skip this step and your emails go straight to spam. I warm up every inbox now—it’s boring but it works. These guides show you exactly how to do it right.

Email Warmup Strategies

Warmup isn’t just about sending more emails gradually. There’s a method to it—engagement patterns, reply rates, the right tools. I’ve tested different approaches and some work way better than others. Start here before you scale.

📌 Start here: 10 email warmup strategies that boost inboxing (Pro List 2026)

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Inbox Placement & Testing

Are your emails actually landing in the inbox or going to spam? I used to guess. Now I test before every campaign. Inbox placement testing saved me from launching campaigns that would’ve tanked my reputation.

📌 Start here: Inbox placement testing before campaigns launch (Start Here)

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Improving Deliverability

Deliverability is the sum of everything—authentication, warmup, list quality, content, sending patterns. When something’s off, your emails suffer. These guides help you diagnose issues and fix them fast.

📌 Start here: Improve cold email deliverability with these 7 fixes (2026 Update)

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3. Email Bounces & Deliverability

Before you worry about copywriting or subject lines, you need to actually land in the inbox. I learned this the hard way after watching campaigns tank because of bounce issues I didn’t even know I had. Get deliverability right first, or nothing else matters.

Understanding Email Bounces

When I first started scaling cold email, bounce notifications confused the hell out of me. Hard bounces, soft bounces, SMTP errors—it felt like alphabet soup. Once I understood what was actually happening behind the scenes, fixing problems became way easier. Start here if bounces are killing your campaigns.

📌 Start here: Email Bounces: Everything You Need to Know (2025 Guide)

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Bounce Rates & Metrics

What’s a good bounce rate? I used to have no idea. Turns out, even a few percentage points can wreck your sender reputation over time. These guides help you understand the numbers that actually matter and what benchmarks to aim for.

📌 Start here: What is a Good Bounce Rate for Cold Email Campaigns? (2025 Benchmarks)

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Reducing Bounce Rates

Knowing you have a bounce problem is one thing. Fixing it is another. I’ve tested pretty much every tactic out there to lower bounce rates, and some work way better than others. Here’s the stuff that actually moves the needle.

📌 Start here: 5 Ways to Lower Your Email Bounce Rate (Proven Methods)

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4. Email Verification & List Hygiene

Bad email addresses are campaign killers. One batch of unverified leads can tank your domain reputation for months. I verify every single list before sending now—no exceptions. It’s the cheapest insurance you can buy for your outreach.

Email Verification Basics

How do you know if an email address is real without actually sending to it? That question drove me crazy when I started out. Turns out there are smart ways to validate emails before you ever hit send. These guides walk you through the fundamentals.

📌 Start here: How to Check If an Email Address is Valid Without Sending an Email

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Advanced Verification

Catch-all domains, disposable emails, spam traps—these edge cases tripped me up for way too long. They look like valid addresses but can destroy your deliverability. Once you know how to spot them, you’ll save yourself a ton of headaches.

📌 Start here: How to Verify Catch-All Domain Emails Without Risking Deliverability

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Email Checkers & Tools

I’ve tried a bunch of email verification tools over the years. Some are great, some are garbage, and pricing varies wildly. Here’s what I’ve learned about picking the right tool and actually using it to keep your lists clean.

📌 Start here: 10 Best Email Checker Tools: Complete Comparison Guide

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5. Cold Email Strategy & Outreach

Deliverability gets you in the inbox. Strategy gets you replies. I’ve tested hundreds of variations on subject lines, openers, CTAs, and follow-up sequences. The gap between what works and what doesn’t is massive—and most advice out there is recycled garbage.

Cold Email Fundamentals

Writing cold emails that don’t suck is harder than it looks. Most people either sound like robots or come across as desperate. I spent years figuring out what actually resonates with busy people who get tons of emails. These guides cover the core principles.

📌 Start here: How to Write a Cold Email That Gets Responses (Even From Busy People)

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Subject Lines & Openers

Your subject line decides if your email gets opened. Your first line decides if it gets read. I’ve A/B tested more subject lines than I can count, and the winners usually surprise me. Forget clickbait—here’s what actually performs.

📌 Start here: 13 Cold Email Subject Lines That Actually Get Opened (No Clickbait)

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Follow-ups & Sequences

Most of my meetings come from follow-ups, not first emails. But there’s a fine line between persistent and annoying. I’ve dialed in sequences that land meetings without making me look desperate. Timing and tone matter more than you think.

📌 Start here: 5 Email Follow-Up Sequence Examples That Land Meetings on Autopilot

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6. Professional Email Writing

Cold email skills translate to all professional communication. Whether you’re emailing a prospect, a client, or your boss, the same principles apply: be clear, be human, and get to the point. These guides help you nail the basics of business email.

Email Greetings & Openers

I cringe every time I type ‘Hope you’re well.’ It’s meaningless filler that everyone uses. Better openers exist, and they can set the tone for your entire email. First impressions happen fast—don’t blow yours on a generic greeting.

📌 Start here: 9 Email Greetings That Don’t Start With “Hope You’re Well”

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Email Sign-offs & Closings

How you end an email matters more than most people realize. The wrong sign-off can undercut everything you just wrote. I’ve tested different closings and some consistently outperform others. End strong, not weird.

📌 Start here: How to Sign Off on an Email Without Sounding Awkward

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Formal Email Writing

Sometimes you need to be more buttoned-up. Job applications, executive outreach, formal requests—they all need a different tone. Here’s how to write professional emails that don’t sound stiff or robotic.

📌 Start here: How to Write a Formal Email (2025 Standards)

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