How to verify business emails in bulk with Aeroleads for higher deliverability

If you’re sending cold emails or handling outreach for your company, you already know the pain of bounced messages and getting flagged as spam. Bad email addresses aren’t just annoying—they can tank your sender reputation and waste your time. If you need to clean up a big list of business emails before hitting send, this guide is for you.

We’ll walk through how to verify business emails in bulk using Aeroleads, what actually matters for deliverability (and what doesn’t), plus tips to avoid common traps.

Why Bother With Email Verification?

Let’s be blunt: most B2B email lists are a mess. Even if you pulled addresses yourself, people change jobs or companies close. If more than a few percent of your emails bounce, you’re sending a big red flag to email providers—think Gmail, Outlook, etc. End result? You land in spam more often, or even get blocked.

Verifying emails in bulk can:

  • Cut down on bounces (keeps your sender reputation safe)
  • Stop you from emailing dead leads
  • Save money on email sending tools (most charge by the email)
  • Make your analytics less noisy (so you know what’s actually working)

Ignoring this step is like mailing out postcards with half the zip codes wrong. Some might get through, but it’s a waste.

Step 1: Gather and Prepare Your Email List

First, get your list together. Maybe it’s a spreadsheet from LinkedIn scraping, a CRM export, or somewhere else. The format doesn’t matter much, but a simple CSV works best. Here’s what you should do:

  • Stick to business emails. Personal addresses (Gmail, Yahoo, Hotmail) are more likely to get flagged.
  • Clean up duplicates. No point verifying the same address twice.
  • Remove obvious fakes. Stuff like test@company.com or info@ addresses rarely lead to real conversations.
  • Keep it simple. One column for emails is usually enough. If you have names and companies, keep those too—they can be handy later.

Pro tip: The more you prep now, the less time you’ll spend fixing mistakes later.

Step 2: Sign Up and Set Up Your Aeroleads Account

Aeroleads isn’t the only email verifier out there, but it’s built for B2B prospecting and integrates with a lot of CRM tools. If you haven’t used it before, you’ll need to:

  1. Go to Aeroleads and sign up for an account.
  2. Confirm your email and log in.
  3. Pick a plan. Aeroleads isn’t free, but you can start with a trial or pay-as-you-go credits for small lists. If you’re only verifying a few hundred emails, you probably don’t need a monthly subscription.

What works: Aeroleads is straightforward—no weird hoops to jump through, and the UI is simple enough for non-tech folks.

What to skip: Don’t bother with integrations or browser plugins yet if all you want is a cleaned-up list. Focus on verification first.

Step 3: Upload Your Email List

Now it’s time to get your emails into Aeroleads. Here’s how:

  1. Find the Bulk Email Verification Tool. Once logged in, look for “Bulk Email Verification” or similar wording in the dashboard.
  2. Upload your CSV. Drag-and-drop works, or use the upload button. Make sure your file’s columns match what Aeroleads expects. If you get an error, double-check that your file has a column with emails—no extra formatting needed.
  3. Map the fields. Aeroleads may ask you to confirm which column contains emails. Pick carefully—if you mix up columns, you’ll get junk results.
  4. Start the verification. Click to start, and the tool will chew through your list.

How long does it take? For a few hundred emails, usually just a couple minutes. For big lists (10,000+), it might take longer, but you can let it run in the background.

Heads up: Don’t close your browser tab until the upload is confirmed. After that, you can walk away.

Step 4: Review and Filter the Results

Once Aeroleads finishes, you’ll get a report for each email. Here’s what you’ll see (and what it means):

  • Valid: The email exists and can receive mail. Great, keep these.
  • Invalid: The address is fake, misspelled, or the domain is dead. Ditch these.
  • Catch-All: The domain accepts all emails, but you can’t be sure the address is real. These are a gamble—sometimes they work, sometimes not.
  • Unknown: Couldn’t verify. Maybe the mailbox is full, or the server didn’t respond. Up to you, but these are risky for big sends.

What to actually send to: Stick to “Valid” emails for best results. If your list is small and you’re desperate, you can try “Catch-All” addresses, but expect more bounces.

Exporting: Download the cleaned-up list as a new CSV. Most people just delete the bad ones, but you could also tag them in your CRM as “do not email.”

Pro tip: Save your results, not just the original file. If you ever want to re-verify, you’ll thank yourself for keeping track.

Step 5: Import the Clean List Into Your Email Tool

This is the part most people rush. Don’t just upload your new list and blast away. Instead:

  • Import only the “Valid” emails. Don’t mix in the junk you just filtered.
  • Double-check formatting. Some email tools are picky; make sure your CSV matches what they want (no weird characters, correct headers, etc.).
  • Test with a small batch. Send a handful of emails first to make sure everything works. If you see bounces, stop and check what slipped through.

What works: Most email tools (Mailshake, Outreach, HubSpot, etc.) play nice with CSVs. If you’re doing this by hand, it’s tedious but straightforward.

What doesn’t: Never just “select all” and email everyone, especially if you haven’t emailed these people before. That’s a quick way to get flagged as spam.

What Actually Improves Deliverability (And What Doesn’t)

Let’s clear up some common myths about deliverability:

  • Email verification helps, but it’s not magic. You still need good content, a warm-up period for your sending domain, and to avoid spammy phrases.
  • List quality matters more than list size. A small, clean list beats a giant, messy one every time.
  • Tools can’t fix a bad sender reputation. If you’ve already been flagged as spam, verifying emails won’t save you. You’ll need to warm up a new domain.
  • Ignore “open rate hacks.” Tricks like weird subject lines or fake personalization don’t fix fundamental deliverability issues.

Pro tip: If your bounce rate is above 3-5%, stop and clean your list again. High bounces hurt you more than a small list.

Common Mistakes (And How to Avoid Them)

  • Uploading unverified lists: Don’t assume your CRM is clean. Always verify before a new campaign.
  • Emailing catch-all or unknown results: These addresses are risky. Only use if you’re willing to take the hit.
  • Skipping regular verification: People change jobs all the time. Re-verify every few months if you’re running ongoing campaigns.
  • Blindly trusting any tool: No service catches everything. Expect 95%+ accuracy, not perfection.

Keep It Simple and Iterate

Bulk email verification isn’t glamorous, but it works. Clean your list, stick to valid emails, and monitor your results. Don’t get hung up on every feature or “growth hack”—just get the basics right and improve a bit each time.

If you’re careful, you’ll avoid the worst deliverability headaches and keep your campaigns on track. Less time fighting bounces means more time talking to real people. That’s the part that actually matters.