How to clean a lead list before cold email

Most cold email problems start before the first word is written: the list. Sending to dead companies, duplicate contacts and the wrong people burns your domain reputation and your time. This is the checklist I use on every list before anyone gets a message.

Step 1: Remove what should never be emailed

Duplicates. Same email twice? Keep one. Emailing the same person twice from one campaign looks careless.
Invalid email formats. Missing @, no domain ending, typos like name@company. These bounce.
Dead or parked websites. If the company domain doesn't load, or shows a "domain for sale" page, the business has likely closed or moved.

Step 2: Flag weak contacts

Role inboxes (info@, sales@, hello@, admin@) rarely reach a decision-maker.
Free email providers (Gmail, Outlook, Yahoo) on a "company" lead may be a personal address or a sole trader.
Email domain doesn't match the website. Often an old employer, an agency, or a data error.
Website redirects to a different domain. Often a rebrand or an acquisition. Check you have the current company name.

Step 3: Check fit against your ideal customer

For each row, check four things: industry (does the homepage confirm it?), company size (inside your range?), job title (is this a buyer: owner, founder, partner, director, head of?) and country (can you serve them?).

Step 4: Sort into four tiers

Gold: strong fit and a real buyer. Email first, personalise properly.
Silver: good company, weak contact or one fit issue. Find the right person, then promote to Gold.
Bronze: partial fit. Light nurture or skip.
Cut: dead, duplicate, invalid or clearly off-target. Delete.

Want the scoring rubric as a spreadsheet? Grab the free Gold/Silver/Bronze lead scoring template. Bought a list? Read how to qualify a bought lead list. Exported from Apollo? See Apollo export cleanup.

Do it in two minutes instead of two hours

ListGrader runs every check above automatically. It loads each company website to spot dead and parked sites, flags role, free and duplicate emails, scores fit against your ICP and gives each row a tier with a one-line reason. It exports a CSV ready for Instantly or Smartlead.

Once your Gold list is ready, load it into your sending tool. I use Smartlead for sending, and Instantly works too.

Want Clovis to grade it for you? $200 for up to 1,000 leads, delivered in 48 hours. Hand-checked by a working lead qualifier, Gold/Silver/Bronze/Cut with reasons, ready-to-import file. Payment via Wise after the job is confirmed. See how it works →

Grade your list free (100 rows, no signup) →