Step by step guide to importing contact lists into Mailreef for B2B sales

If you’re running B2B sales, you know that a clean, well-organized contact list is half the battle. But even with the fanciest tools, getting your contacts into the right system can be a headache. This guide is for anyone who’s ready to import a list of leads into Mailreef, hoping to actually send emails that land and get responses—not just to check a box for “outreach done.”

You’ll get a walk-through of the actual steps, what works, where things go sideways, and some reality checks along the way. No hand-waving, just straight talk.

1. Get Your Contact List Ready

Before you even log in to Mailreef, you’ll want to tidy up your contact list. This isn’t just busywork—if your data’s a mess, you’ll waste time fixing mistakes later and possibly burn good leads.

What you need: - A spreadsheet (Excel, Google Sheets, or CSV file) - The basics: First Name, Last Name, Email, Company. (More fields are fine, but don’t overthink it.)

Pro tips: - Ditch the fluff. Don’t import columns you’re never going to use. “Fax number”? Seriously? - Double-check emails. One typo can tank your deliverability or just make you look sloppy. - Remove obvious junk. Test emails, competitors, or anyone who’d be annoyed to hear from you. - Watch for duplicates. Mailreef tries to handle these, but it’s easier to clean up now.

Reality check:
Don’t sweat about having a perfectly complete record for every contact. Missing a job title or phone number? Not a big deal. But emails and first names should be solid.

2. Save Your List as a CSV File

Mailreef eats CSV files for breakfast. If you’re working in Excel or Google Sheets, here’s how to export:

  • In Excel:
    Click File > Save As > Choose CSV (Comma delimited) (*.csv).

  • In Google Sheets:
    Click File > Download > Comma-separated values (.csv, current sheet).

Name your file something clear, like prospects-june2024.csv. Avoid spaces and weird characters.

What NOT to do: - Don’t import an XLSX, PDF, or anything but CSV. - Don’t try to copy-paste hundreds of rows into Mailreef. Use the import feature—it exists for a reason.

3. Log in to Mailreef and Find the Import Tool

Now head over to Mailreef and sign in.

  • Go to the “Contacts” section (sometimes called “Leads” or “People”—depends on your setup).
  • Look for a button that says something like “Import,” “Upload Contacts,” or “Add List.”
  • If you can’t find it, check the sidebar or the top navigation. Still lost? Use the help icon—no shame in that.

Heads up:
If you’re on a trial plan or the cheapest tier, double-check if there are limits on how many contacts you can import. Some platforms hide this behind paywalls.

4. Upload Your CSV File

Click the “Import” or “Upload” button and select your CSV file.

You’ll usually see: - A preview of your contacts—Mailreef will try to match your columns to its own fields. - A chance to map columns if it gets confused (e.g., if you called the email column “Work Email” instead of just “Email”).

Tips for a smooth import: - Make sure every contact has an email address. Blank emails usually get skipped. - Check that names aren’t swapped (first/last name in the wrong columns). - If you have custom fields (like “Industry” or “Lead Source”), you may need to create those in Mailreef first so the data has somewhere to go.

Don’t panic:
If a few rows error out, it’s not the end of the world. Focus on the 95% that work, then fix the outliers later.

5. Review and Fix Import Errors

Even with a clean list, there’s usually some hiccup. Mailreef should show you a summary: how many contacts were imported, skipped, or errored.

Common issues and fixes: - Duplicate contacts: Mailreef might skip these or merge them, depending on settings. - Bad email formats: Go back to your CSV, fix them, and re-upload (or just delete those rows if they’re not worth it). - Missing required fields: If Mailreef insists on a company name and you don’t have it, you’ll need to add a placeholder.

Pro tip:
Don’t waste hours chasing down every missing phone number. Get the main batch in, then move on. You can always update later if you strike gold with a lead.

6. Tag or Segment Your Contacts (Optional, but Smart)

If you’re importing a generic list, skip this. But if you have different types of contacts—by industry, region, or campaign—it pays to tag or segment them during import.

How to do it: - In Mailreef, you’ll usually see an option to add a tag or assign contacts to a list/group during the import. - Use simple, descriptive tags: webinar-june, cold-leads, vip-clients.

Why bother? - Makes it way easier to send targeted emails later. - Helps you avoid blasting the wrong people with the wrong message.

What not to do:
Don’t create a tag for every possible attribute (“likes-golf”, “sent-birthday-coupon”) unless you’re actually going to use them.

7. Confirm Everything Imported Cleanly

Once the import finishes, spot-check your contacts:

  • Look for obvious weirdness: names in all caps, misplaced columns, missing emails.
  • Search for a few known contacts to make sure they landed where you expect.

If something’s off, it’s almost always a CSV formatting issue. Go back, tweak, and try again. Don’t be afraid to delete your import and redo it—better now than sending 500 emails with “Hi [FIRSTNAME],” as the opener.

8. Mind Your Deliverability

This isn’t technically part of importing, but it’s where most B2B campaigns flop.

Some hard truths: - If your list is old, scraped, or bought, expect bounces. Clean it using an email verification tool before importing. - Don’t blast your full list on day one. Warm up your domain and send in smaller batches first. - If you see a high bounce rate or lots of spam complaints, stop and revisit your list quality.

Ignore the hype:
No tool can magically make a bad list perform well. Good data beats fancy features every single time.

9. Start Your Outreach—But Keep It Simple

Now that your contacts are in Mailreef, resist the urge to overcomplicate your first campaign.

  • Pick a clear segment or tag, write a straightforward message, and send a small batch.
  • Watch for replies, bounces, and unsubscribes. Tweak as you go.

You don’t need to automate everything or build a 12-step sequence out of the gate. Simple, personal messages work best, especially in B2B.

Wrapping Up: Don’t Overthink It

Importing contacts into Mailreef isn’t rocket science, but it pays to do it right. Clean your list, import as CSV, tag what matters, and don’t get bogged down chasing perfection. The best approach? Keep things simple, launch fast, and tidy up as you go. The magic’s not in the import—it’s in what you do with your list next.