Abandoned cart email subject lines that get the click

What makes a good abandoned cart subject line?

Clarity. Someone who left a cart was close to buying. The subject line's only job is to remind them what they wanted and give them a reason to open now.

The most common subject line mistake I see is being too crafty. People who buy from your emails want to know what they'll get and where. That applies even more in a cart email, where the person already knows your brand.

Across 2,821 campaigns from 7 brands, subject lines that read like news did better than ones written in brand voice, and vague questions did worst. Shorter lines often help too. For one sports tech brand, subject lines of 20 characters or fewer got more than 2x the clicks of lines between 41 and 60 characters. That's one brand, so test it on yours.

The same rules apply to campaigns. More in email subject line best practices.

What should each email in the flow say?

Give every email a different angle. If all three say "You forgot something," the third one adds nothing.

Email 1: the reminder - "Your cart is saved" - "Still thinking it over?" - "You left the [product] behind"

Email 2: the reassurance - "Here's what people say about the [product]" - "Questions about your order?" - "Why customers reorder the [product]"

Email 3: the reason to act now - "Your cart expires soon" - "Free shipping on your order ends tonight" - "Last call on your cart"

These are starting points, not proven winners. Your own flow data decides which angle works for your list.

Don't stop at three just because it feels like enough. Across 4 brands, cart abandon email #5 still earned $0.25 per person, the same as email #3. Keep cart flows long and keep giving each email a new reason to come back.

Should you put the product name in the subject line?

It's worth testing, because the product name is the most specific thing you can say. Klaviyo lets you pull event data, like the product someone added, into messages in flows triggered by Added to Cart or Started Checkout. Klaviyo's help center gives this example for the first product's title on a Shopify Started Checkout event:

{{ event.extra.line_items.0.product.title }}

A few cautions from Klaviyo's help center:

• Event variables only work in flow messages triggered by a metric, not in campaigns.
• They're case-sensitive. The slightest difference from what shows in the preview can break them.
• The exact path depends on your integration and the event, so check it in the flow editor's preview before you use it.

Always preview the email with a real event before turning it on. A subject line that renders as blank or shows raw code is worse than a generic one.

Should abandoned cart subject lines be questions?

Mostly no. Across brands, question subject lines earned about 18% less revenue per email. My guess, and it's only a guess, is that questions reach people who are interested but confused, not people ready to buy.

A specific question can still work as one of your tests ("Did the [product] sell out?" is more concrete than "Ready to treat yourself?"). But if you're writing your first version, lead with a statement.

Should you mention a discount or a deadline?

A deadline, yes, when it's real. A discount, only if it fits your offer strategy.

Good reasons to come back now:

• Shipping cutoffs. In November and December, put cutoff lines in abandonment emails if you're far enough ahead and your brand is ready. Plenty of brands aren't prepared for this, so plan your dates first.
• Gifting. Gifting lines belong in the customer branches of abandonment flows. They give a reason to finish the order. It's obvious for consumer tech or jewelry, less direct for food and beverage.
• Low stock or restocks, when they're true.

If you do use an offer, save it for a later email so the first reminder isn't trained to wait for a code. More on that in email discount strategy.

Why test your abandonment emails first?

Because that's where you learn what gets people across the finish line when they're close to buying. Abandonment emails and campaigns are where I'd start testing.

How to run a subject line test in a cart flow:

1. Pick one email and test one change (statement vs question, short vs long, product name vs none).
2. Judge a subject line test on opens as a first signal, then check clicks and revenue.
3. Let at least 100 emails go out before you decide.
4. Repeat what wins before you treat it as a rule.

The Klaviyo side of setting it up is in Klaviyo A/B testing.

Is Smart Sending stopping your cart emails?

Check this before you rewrite a single subject line. Smart Sending is built to hold back a message from people who were messaged recently. That's fine for normal campaigns, but I keep it off on automations so people don't miss critical reminders.

A haircare brand had Smart Sending left on for its abandoned checkout emails. Many people never got their reminders, and the brand lost a lot of revenue. The best subject line in the world doesn't help if the email never sends. More in Klaviyo Smart Sending.

Cart vs checkout vs browse: do the subject lines change?

Yes, because the intent changes.

• Browse abandonment: they looked, didn't add anything. Softer: "Still looking?" See browse abandonment emails.
• Cart abandonment: they added something. Name it if you can.
• Checkout abandonment: they started paying. Be the most direct here: "Your order is almost done." See abandoned checkout emails.

If you're not sure which flow you're running, start with abandoned cart vs abandoned checkout.

FAQ

WRITTEN BY Jack White

Founder of Bardown Digital, a Chicago-based Klaviyo email and retention agency for Shopify brands. He's worked with brands doing $500K to $100M a year, with $100M+ in email-attributed revenue across them.

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