Hard bounce vs soft bounce Klaviyo guide: what gets suppressed and what to fix

If you've searched hard bounce vs soft bounce Klaviyo, the answer comes down to one word: permanent. A hard bounce means the email can never be delivered to that address, so Klaviyo suppresses it right away. A soft bounce means “not right now”, so Klaviyo keeps trying, and only suppresses the address after 7 soft bounces in a row.

That's straight from Klaviyo's guide to bounced emails. Simple enough. The trouble is what happens in between. Every bounce is a signal to Gmail, Yahoo and Outlook that you don't look after your list. Seven tries is a lot of signals.

So here's the hard bounce vs soft bounce Klaviyo playbook I use: the tricks first, then the rules, the healthy numbers and a fix for every bounce category.

6 tricks to keep Klaviyo bounces near zero

1. Don't wait for soft bounce number seven

Klaviyo's own bounce rate guide says each bounce affects your deliverability, even before the automatic rule kicks in. Its fix: build a segment of people with at least 4 bounced emails in the last 90 days who can still receive email marketing. The 4 don't need to be consecutive. Exclude that segment from campaigns, or suppress it.

2. Turn on double opt-in

Klaviyo “strongly” suggests keeping double opt-in enabled on your lists. A person who confirms their address can't have typed it wrong. That kills most hard bounces before they're born. Check it under the list's Settings > Consent.

3. Quarantine giveaway sign-ups

Contest entrants often use an inbox they never check. Klaviyo warns that when those fill up, your emails start to bounce. Put giveaway profiles on a separate list, and only move people who engage to your main list.

4. Run a sunset flow

Old, silent addresses go stale, and stale addresses bounce. Klaviyo lists a sunset flow as a fix for invalid address bounces because it removes unengaged people before their mailbox dies. My Klaviyo sunset flow guide has the exact segment and timing.

5. Read the category, not just the count

“2% bounced” tells you nothing about the fix. Klaviyo's deliverability hub (Analytics > Deliverability > Email > Bounce details) shows all 11 bounce categories by inbox provider. A spike in “Technical” at one provider is a DNS job. A spike in “Invalid address” is a list job.

6. Never delete bounced profiles

It feels tidy. It isn't. Klaviyo's suppression guide says suppressed profiles don't count toward your active profile limit, and deleting them skews your segments and reports. Keep them. They cost nothing.

Hard bounce vs soft bounce Klaviyo cheat sheet

To check a single person, open their profile, find the bounced email event in the activity log, open Activity details and look at Bounce Type. For a campaign, the Recipient activity tab shows category, reason and type for every bounce.

What is a good bounce rate in Klaviyo?

Klaviyo's deliverability metrics guide sets these ranges:

Klaviyo suggests judging these over the last 30 days, not one send. One bad campaign can happen. A trend is the problem. But a sharp spike after a single send still deserves a look.

The 7 soft bounce rule, explained

Three details matter, and most people miss at least one:

1. Consecutive. Seven soft bounces in a row. A successful delivery in the middle resets the count to zero.
2. Two years. Only soft bounces from the past 2 years count toward the seven.
3. Lists, too. Once suppressed, the profile is removed from any lists it was on.

Now do the maths for a store that sends twice a week. Seven straight soft bounces can take about three and a half weeks of sends. That's seven failed deliveries Gmail and friends have watched you make. That's why the 4-in-90-days segment exists.

Fix it by bounce category

These fixes come from Klaviyo's bounce guide. Find your top category in the deliverability hub, then start here:

If “Technical” is your problem, my Gmail and Yahoo sender requirements checklist walks through the DNS setup for a Shopify store, and you can test your domain in the email deliverability checker.

Suspicious emails: the bounce you never saw

Klaviyo also flags suspicious emails using hard bounce history across its whole sending network. An address can be flagged even if it never bounced in your account. Klaviyo skips it automatically, and you'll see it under Recipient activity > Skipped as “Skipped: Suspicious Email”.

If you're sure an address is real, Klaviyo asks for proof, usually a screenshot showing a delivered email from that address after the date it was flagged.

Do bounces cost you money?

Directly, a little. Indirectly, a lot.

• Directly: a soft bouncer that hasn't hit the suppression rule is still an active profile, so you pay for it. Once suppressed, it stops counting toward your plan. If a cleanup drops you into a lower tier, Klaviyo says you can pick a lower plan under Settings > Billing. My guide on how to lower your Klaviyo bill covers the rest, and the Klaviyo pricing calculator shows the tier you'd land on.
• Indirectly: Klaviyo warns that high bounces hurt your sender reputation, and a weaker reputation sends more of your emails to spam. That hits every campaign and flow, including the ones that make money. If you want a number on what one inbox is worth, run the email list value calculator.

Your monthly bounce routine (10 minutes)

1. Open the deliverability hub and check the 30-day bounce rate. Under 1%? Good.
2. Look at the top 2 bounce categories and the inbox provider behind them.
3. Check the size of your chronic soft bounce segment. Growing? Suppress it.
4. Confirm double opt-in is still on for every sign-up list.
5. Make sure your sunset flow is live and its segment is updating.
6. Note your bounce rate next to your unsubscribe and spam rates. If you're testing new content, treat all three as guardrails. My Klaviyo A/B test sample size guide explains why.

That's the whole job. Hard bounces take care of themselves. Soft bounces need you to step in early. Do that every month and your bounce rate stays boring, which is exactly what you want.

FAQ

Keep reading