Why Emails Go to Spam in the First Place
Email providers like Gmail, Outlook, and Yahoo use smart filters to protect users from spammy content. These filters look at a combination of factors:
Your domain reputation
The words and formatting in your email
How many emails you’re sending—and how fast
Whether people open, reply, or mark you as spam
Whether your technical setup checks out
If anything looks off, even slightly, your email could go straight to the spam folder.
Step 1: Set Up Your Domain Properly
Before you send a single cold email, make sure your domain is configured correctly.
Here’s what you need:
A mirror domain (like
outreach.yourcompany.com)Proper DNS records: SPF, DKIM, and DMARC
A warmed-up sending reputation (gradually ramping up your volume)
A dedicated tool or inbox that separates cold emails from your main domain
👉 Not sure how to do this? Check out our DNS setup guide.
Step 2: Use Deliverability-Friendly Language
Content plays a huge role in whether your email hits the inbox or not. Even if your technical setup is perfect, using too many “trigger words” can flag your message as spam.
🚫 50 Common Spam Trigger Words to Avoid
Words that sound scammy:
Free, Guarantee, Risk-free, Winner, Promise you, 100% guarantee,
Hard-sell phrases:
Buy now, Act fast, Limited time, Don’t miss out, Exclusive deal, Save big, Instant access
Financial red flags:
Earn money, Investment, Extra cash, Eliminate debt, Make money,
Medical claims:
Miracle, Cure, Weight loss, Anti-aging, Enhance
Urgency or pressure:
Urgent, Final notice, Act immediately, This won’t last, Last chance, Time-sensitive, Hurry
Use these words carefully—especially in subject lines and intros. If it feels like a sales pitch, it probably reads like one too.
Step 3: Write Like a Human, Not a Marketer
Spam filters are trained to spot robotic, salesy emails. People are too.
What works instead:
Keep it short, simple, and personal
Sound like someone starting a conversation—not closing a deal
Use natural language and one clear call to action
Bad example: “Hurry! This exclusive offer won’t last!”
Better example: “Hey, saw you’re hiring—open to a quick chat?”
Focus on Value, Not Hype
Frame your message around them, not you
Be clear and honest about your offer
No clickbait subject lines
Structure That Works:
Subject: Direct, relevant, and curiosity-driven
Opener: Personalized, shows relevance
Body: Short pitch with clear outcome
Call to action: Light, non-pushy (“Open to a quick chat?”)
Step 4: Send Smart
You can have great emails and still land in spam if you’re sending them the wrong way.
Don’t:
Blast 500 emails/day from a cold domain
Use identical templates for every contact
Using link trackers or URL shorteners too early
Overusing images, attachments, or formatting
Do:
Start small (20–50 emails per day per inbox)
Personalize every message (first lines, context, value)
Ramp up volume gradually as your domain warms
Step 5: Test, Track, and Tune
Cold email success is about consistency—and knowing what’s working.
Tools worth using:
Mail-Tester – check for spam words and formatting issues
GlockApps – test your inbox placement
Warmup tools – keep your reputation strong
Metrics to monitor:
Open rate (healthy = 40%+)
Reply rate (strong = 8–12%)
Bounce rate (safe = under 5%)
Spam complaints (ideal = under 0.1%)
Bonus: Keep Your Lists Clean
Your message might be perfect—but if you’re emailing bad data, none of it matters.
Always verify email addresses before you send (Alsona enriches your lists with cleansed data)
Use tools like LinkedIn filters and enrichment platforms to build targeted, verified lead lists
Final Thoughts
Cold email is still one of the most powerful growth channels—but only if your messages make it to the inbox. Avoiding spam isn’t about tricking filters. It’s about building real conversations from a place of relevance, clarity, and trust.
Clean setup. Clean copy. Clean list. That’s the formula.