Know Reply vs Klaviyo

You Send the Campaign. They Reply. Then What?

You send a Klaviyo campaign to 15,000 subscribers. Opens look good. Clicks are solid. Revenue is tracking.

But some customers don’t click. They reply.

“Does this come in navy?” “Will this fit if I’m usually a size 8?” “Can I combine this with the discount from last week?”

Those replies leave Klaviyo entirely. They land in your brand’s inbox, at support@yourbrand.com or wherever your reply-to points. Klaviyo doesn’t track them, can’t trigger flows from them, and has no record they happened. As far as Klaviyo is concerned, those customers didn’t engage at all.

Each reply is a customer with one question between them and checkout. Right now, nobody is answering.

Why Klaviyo Can’t See Its Own Replies

This isn’t a missing feature. It’s how ESPs were built.

Klaviyo has two separate systems. The marketing pipeline sends campaigns, flows, and automations (outbound). The Helpdesk pipeline handles support tickets that arrive through specific channels (inbound). These two pipelines don’t connect.

When a customer replies to your Black Friday campaign, that reply goes to your configured reply-to address. It doesn’t enter Klaviyo Helpdesk. It doesn’t reach Customer Agent. It doesn’t show up in campaign analytics.

Klaviyo’s Customer Agent (launched September 2025) is a solid product for support tickets routed through the Helpdesk. But it operates in the support pipeline, not the marketing pipeline. Campaign replies never reach it.

How Know Reply Fills the Gap

Know Reply monitors the inbox where Klaviyo replies actually land. The workflow:

1. Klaviyo sends a promotional email to your list
2. Customers reply with buying questions: sizing, availability, shipping, returns
3. Those replies arrive in your brand’s inbox
4. Know Reply picks up each reply, understands the question using your website content, and responds within seconds
5. The customer gets an answer while they’re still ready to buy

Nothing changes in Klaviyo. Your campaigns, flows, and automations stay the same. Know Reply handles what happens after the customer hits reply.

Where Klaviyo Wins

Klaviyo is the dominant ecommerce ESP for good reason:

• Shopify data integration. Customer profiles, order events, product catalogs, and browsing behavior sync natively. No connectors needed.
• Segmentation depth. Build audiences from purchase history, engagement, and predicted lifetime value. Core ESP functionality that Know Reply doesn’t touch.
• Campaign and flow builder. Visual automations, A/B testing, send-time optimization, and revenue attribution. Klaviyo’s bread and butter.
• SMS and multi-channel. Coordinated email + SMS campaigns from a single platform. Know Reply handles email only.
• Revenue attribution. Track exactly how much each campaign or flow generates. Know Reply measures reply metrics, not marketing revenue.

You need an ESP. Klaviyo is likely the right one. The comparison is narrow: what happens when customers reply to the emails Klaviyo sends.

What Customer Agent Actually Does

Customer Agent handles support well. Here’s where it works and where it stops:

Works:

• Support inquiries routed through Klaviyo Helpdesk
• Shopify order lookups for tracking and status
• Product recommendations from your catalog
• Escalation to human agents
• Web chat (GA), SMS (GA), email (beta)

Doesn’t work for campaign replies:

• Can’t intercept replies to campaigns or flows. They go to your reply-to address, outside Klaviyo’s system.
• English-only (other languages on the roadmap)
• Requires manual knowledge base setup in Helpdesk
• No draft review before sending

This separation is deliberate. Klaviyo designed their marketing and support systems as distinct pipelines.

The Pricing Difference

Klaviyo’s ESP runs ~$100–110/mo for 5,000 contacts. Customer Agent adds $50/mo for up to 75 conversations, with usage billing above that (contact Klaviyo for overage rates). These costs stack.

Know Reply starts at $20/mo with unlimited AI replies included. No per-conversation charges. Whether the AI handles 10 replies or 5,000 in a month, the price doesn’t move.

	Know Reply	Klaviyo Customer Agent
Base price	Starts at $20/mo	$50/mo (75 conversations)
AI replies	Unlimited	Per-conversation above 75
Per-resolution fees	None	Usage billing above minimum
Pricing model	Contact-based tiers	Per-conversation + ESP base

Note: You still need Klaviyo for sending campaigns. These products serve different purposes and their costs stack. See our Klaviyo integration guide for the recommended setup.

Who Should Choose What

Keep Klaviyo (you already should)

Klaviyo is the best ecommerce ESP. Use it for campaigns, flows, segmentation, SMS, and attribution. Nothing here changes that.

Add Know Reply when

• Customers reply to your campaigns and nobody answers
• You’re using a no-reply address and want to stop losing those conversations
• You want AI email replies without per-conversation billing
• You need replies handled in multiple languages

Consider Klaviyo Customer Agent when

• You route support tickets through Klaviyo Helpdesk
• You want a single vendor for ESP + support
• Your volume stays under 75 conversations per month

Use all three

The most complete setup: Klaviyo for outbound marketing, Customer Agent for Helpdesk support tickets, Know Reply for campaign replies. Each handles what it was built for.

Stop Losing Campaign Replies

No-reply addresses exist because marketing teams never had a way to handle reply volume. That’s no longer true.

If you’re using a no-reply address in Klaviyo, customer replies are bouncing right now. Those customers have questions that stand between them and a purchase. Know Reply catches those replies and answers them, turning silence into sales.

Switch to a monitored reply-to address in Klaviyo, connect it to Know Reply, and stop losing customers who were ready to buy. For more on this, see The No-Reply Inbox Problem. For ecommerce-specific use cases, see Know Reply for E-Commerce.