🧨The Risk of Using Purchased Email Lists
You've bought a list of 100,000 contacts. Tempting, right?
But here's what could happen next:
- You send a campaign.
- Bounce rates spike >10%.
- Your domain gets flagged.
- You end up on a blacklist—or worse, face a GDPR complaint.
Let's avoid that.
🧼Step-by-Step: How to Clean a Purchased Email List
1. Run Email Validation Before Sending
Before importing anything into Mailchimp or Brevo:
- ✅ Remove invalid syntax
- ✅ Filter out disposable domains
- ✅ Detect spam traps or catch-alls
- ✅ Check for greylisting or blacklisting
- ✅ Score deliverability
📌 Use a tool like Lero to do this in seconds.
2. Segment Unknown/Low-Risk Leads
Don't send the same cold email to everyone. Segment your list:
| Segment | Risk Level | Action |
|---|---|---|
| Valid + score > 90 | ✅ Low | OK to outreach |
| Valid + score 70–90 | ⚠️ Medium | Test gradually (warming) |
| Catch-all or unknown | ❓ High | Use LinkedIn or enrich |
| Invalid / trap | 🚫 Critical | Remove immediately |
3. Use Custom Domains & Warmup
Never blast from your main domain. Instead:
- Set up a subdomain (news.yourbrand.com)
- Use warm-up tools (Mailwarm, Instantly, Lemwarm)
- Start with low volume sends
This shields your main domain from getting flagged.
4. Add GDPR-Safe Copy
Avoid copy that screams spam. Instead:
- Be transparent: "You're receiving this because…"
- Offer easy opt-out
- Link to your privacy policy
- Use a legit reply-to email
GDPR isn't just about consent—it's also about intent and tone.
5. Track Deliverability Metrics Religiously
| Metric | Target |
|---|---|
| Hard bounce | < 2% |
| Open rate | > 20% |
| Complaint rate | < 0.1% |
| Inbox rate | > 90% (via tests) |
Anything over those thresholds = fix it before you burn your domain.
⚖️Is Buying Lists Even Legal?
Under GDPR, sending to purchased lists is not illegal if:
- There's a legitimate interest
- You provide clear opt-out
- You include privacy & contact details
Still, most vendors don't comply. Cleaning the list is your job.
💡Lero Helps You Clean Lists—Fast, Cheap, GDPR-Safe
Validate 100,000 emails in seconds
Lightning-fast processing
Filter risky records
Before hitting "Send"
No data stored
GDPR by design
From $0.0003/email
(first 500 free)
👇 TL;DR
"Cleaning a purchased list isn't optional. It's your only shot at deliverability—and compliance."
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