Data Hygiene & List Cleaning
Clean data is the foundation of successful outreach. Poor data quality causes bounces, spam complaints, and reputation damage.
Why Data Hygiene Matters:
- Bounce rates above 3% damage your sender reputation.
- Invalid emails waste your daily sending quota.
- Outdated contacts result in spam complaints (people at new companies).
- Duplicate records cause embarrassing double-sends.
Before Importing (Pre-Import Cleaning):
- Remove obvious junk — blank rows, test entries, personal emails (gmail.com, yahoo.com for B2B campaigns).
- Standardize formatting — consistent name capitalization, remove extra spaces.
- Verify email format — every email must contain @ and a valid domain.
- Remove role-based emails — info@, sales@, support@, admin@ have high bounce and complaint rates.
- Check for suppressed domains — remove emails from domains on your blocklist.
Using WarmySender's Built-in Tools:
- Email Verifier — Verify all imported emails before sending. Status: Valid, Invalid, Risky, Unknown.
- MX Validation — During import, emails with invalid domain DNS are automatically flagged.
- Deduplication — Import automatically skips duplicates (by email within your workspace).
- Suppression List — Matches against your blocklist during import.
Ongoing Maintenance:
- Re-verify lists older than 30 days — email addresses go stale at ~2% per month.
- Review bounced contacts monthly — remove or re-verify them.
- Monitor your bounce rate in Analytics. If it exceeds 3%, clean your lists immediately.
- Export your suppression list periodically and cross-reference with active prospect lists.
- Remove prospects who have been contacted 3+ times with no engagement.
Bounce Shield — already on, nothing to enable:
• Campaigns pause themselves when bounce rates go above their limit (5% by default), once there are at least 50 sends to judge on.
• Bounced addresses are added to your blocklist automatically and no campaign emails them again.
Neither of those can be switched off — they run on every campaign in every workspace. What Settings → Bounce Shield adds is a STRICTER limit of your own, applied across the workspace (we always use whichever is lower, so it can only tighten protection), plus an email to the workspace owner when a campaign is paused. Why a campaign paused and how to clean the list before resuming: warmysender.com/documentation/why-did-my-campaign-pause-for-bounces
Best Practices:
- Verify before you send — always. It costs far less than reputation damage.
- Prefer quality over quantity — 500 verified emails outperform 5,000 unverified.
- Never buy email lists without verification — purchased lists have 20-40% invalid rates.
- Use the Leads Database for pre-verified contacts when possible.