How to create and use custom variables in Lemlist for advanced email personalization

If you’re sending cold emails or running outreach campaigns, you know generic templates don’t cut it. People can spot a mail-merge from a mile away. If you want replies (and not just opens), your emails need to feel like they were written for an actual human being. That’s where custom variables in Lemlist come in. They let you go way beyond the usual “First Name” stuff—so you can drop in details that show you actually did your homework.

This guide is for anyone who’s moved past the spray-and-pray stage. You want to personalize, but you also want to work smart, not spend your life in spreadsheets. I’ll walk you through exactly how to set up and use custom variables in Lemlist, what’s worth your time, and a few things you can skip.

Why Custom Variables Matter (and Where Most Go Wrong)

Most outreach tools let you insert basics like first name, company, maybe job title. That’s fine if you’re blasting generic offers, but it won’t get you far with people who get pitched all day. Custom variables are your chance to stand out by referencing real details—like a recent blog post, mutual connection, or something specific about their business.

But here’s the catch: More variables doesn’t always mean better results. Overcomplicating your emails or stuffing in too much “personalization” can make your message feel forced—or worse, robotic if something breaks. The trick is to use custom variables where they actually add value and keep the rest simple.

Let’s get practical.

Step 1: Understand What Custom Variables Are (and Aren’t)

A “custom variable” in Lemlist is just a placeholder you create—like {{favorite_snack}} or {{recent_award}}—that gets replaced with unique info for each contact. You define it, you fill it in, and you decide where it shows up in your emails.

What they can do: - Let you reference anything that’s unique to each recipient. - Make your outreach more relevant (and less like a template). - Save time once you’ve set them up—no manual copy-pasting for every email.

What they can’t do: - Magically research or fill in details for you (unless you use integrations, but more on that later). - Fix bad messaging. If your offer isn’t right, no variable will save you. - Guarantee higher response rates—personalization helps, but it’s not a silver bullet.

Step 2: Decide Which Custom Variables You Actually Need

Before you dive into Lemlist, take five minutes to sketch out what kind of details would actually matter to your recipients. Don’t just create variables for the sake of it.

Good custom variables: - Something you can find or infer quickly (LinkedIn, company website, recent news) - Details that connect to your offer (“Saw you expanded to Austin—any pain points with hiring?”) - Personal touches that feel natural (“Congrats on your recent funding round!”)

Variables to skip: - Stuff you can’t reliably find for most contacts. - Things that don’t tie back to your message. - Anything that’s just fluff (“Hope you’re having a great week!”—nobody cares)

Pro tip: Start simple. Add one or two custom variables, not ten. You can always expand later.

Step 3: Create Your Custom Variables in Lemlist

Here’s how it actually works inside Lemlist:

  1. Prepare your contact list.
    Use a spreadsheet (CSV or Excel) with each contact as a row. Each column is a variable—standard ones like “First Name,” and your custom ones like “Recent_Post” or “Pain_Point.”

  2. Name your columns clearly.
    The column header will become your variable name in Lemlist, so keep it simple and lowercase. For example:

  3. first_name
  4. company
  5. recent_post

  6. icebreaker

  7. Fill in the details.
    This is the grunt work. Do your research, then fill out your custom columns. If you’re doing serious personalization, this step takes the longest—but it’s also where you stand out.

  8. Import your list to Lemlist.

  9. Go to your Lemlist campaign.
  10. Click “Add leads,” then import your file.

  11. Map your columns to Lemlist variables. Lemlist will recognize standard fields, and for anything new, it’ll prompt you to create a custom variable.

  12. Check your variables.
    Once imported, check a few leads. Make sure your custom data came through. Typos or misaligned columns can break personalization in ugly ways.

Mistake to avoid:
Don’t create custom variables directly in Lemlist without having them in your spreadsheet first. It gets confusing fast. Always start with your data file.

Step 4: Use Custom Variables in Your Email Templates

Now it’s time to put your variables to work.

  1. Write your email as usual, but insert variables where needed.
    In Lemlist’s editor, you can type {{ and see all available variables—both standard and custom. Example:

Hi {{first_name}},

I saw your recent post about {{recent_post}}—loved your take on the challenges in {{industry}}.

Quick question: Are you looking for ways to {{pain_point}} this quarter?

  1. Preview your emails.
    Always preview before you send. Lemlist lets you see each email with real data plugged in. Look for awkward phrasing or missing info.

  2. Set fallback text for missing data.
    Not every contact will have every detail. Lemlist lets you set fallback text (like “your industry” instead of a blank). Format:
    {{custom_variable | fallback:'something generic'}}

Example:
Hi {{first_name}}, I noticed you’re in {{industry | fallback:'your field'}}.

Pro tip:
Don’t overdo it. If you have three custom variables and two of them are empty, your email will look broken. Test with real data, not just the first row of your file.

Step 5: Automate (or Not): When to Use Integrations

Lemlist can pull in data from tools like LinkedIn, CRMs, or enrichment services. This sounds great, but be careful:

When automation makes sense: - You have a large list and need basic info (location, title, company size). - You’re willing to pay for enrichment.

When manual is better: - You want high-quality, truly custom data (like a personal note about a blog post). - You’re emailing a small, high-value list.

Honest take:
Automation is fine for surface-level personalization. But the stuff that gets replies—specific, human-sounding details—usually takes some manual effort. Don’t trust automation to find “recent news” or “icebreakers” that actually sound natural.

Step 6: Test, Tweak, and Don’t Overthink It

  • Send a small batch first.
    Watch for broken variables or weird phrasing. It’s better to catch mistakes before you email 500 people.

  • Look at your replies, not just open rates.
    Did people respond to the personalized bits? Or did they ignore it? Adjust your approach based on real feedback.

  • Iterate.
    If a variable doesn’t add value, drop it. If you find a new angle that gets replies, add it in.

Things to ignore: - Fancy variables for the sake of “advanced personalization.” If it feels forced, your prospect will feel it too. - Overpromising what variables alone can do. They help, but your message and offer still matter more.

Wrapping Up: Keep It Simple, Then Build

Custom variables in Lemlist are a tool—not a magic trick. Start by picking one or two details that actually matter to your audience, set up your spreadsheet, and get your first campaign running. Don’t get lost in the weeds trying to build the world’s most personalized sequence right out of the gate.

As you go, watch what lands and what flops. Keep what works, ditch the rest. That’s how you use personalization to get real replies—not just fancier mail merges.