A merchant of almost six years reports their monthly bill climbed from $80 to $150, with a pause-and-resubscribe quote of $200, and describes it as a roughly 250% increase over their original cost.
Comparison · Klaviyo alternative
A Klaviyo alternative for stores that only need restock alerts
Klaviyo is an excellent full email and SMS marketing platform, and back in stock alerts are one flow inside a much bigger suite. Its pricing scales with how many contacts you have, not how many alerts you send. If Klaviyo is overkill for what you actually need, Kelso is a simpler, alerts-only app priced by send volume instead.
Free to install. Free migration from Klaviyo, we'll move your list by hand.
Sourcing: competitor pricing and review excerpts below were taken from Klaviyo's public Shopify App Store listing and review pages in July 2026. As of July 28, 2026, Klaviyo showed a 4.7 star rating across 2,919 reviews on its Shopify App Store listing. Ratings and pricing change; check their listing before you decide.
Pricing, side by side
What you pay, side by side
| Klaviyo | Kelso | |
|---|---|---|
| Free plan | $0 · up to 250 active profiles, 500 email sends/mo, 150 SMS/MMS credits | 50 sends/mo, unlimited subscribers |
| Entry paid plan | Email plan from $20/mo for 251-500 active profiles, climbing in steps as your contact count grows | $14/mo · 750 sends, flat |
| SMS add-on | $15/mo for up to 1,250 SMS/MMS credits, on top of the email plan | Not offered yet |
| What sets the price | Number of active profiles (contacts) in your account, not send volume | Number of alert emails sent, not contact count |
| Revenue share or overage fees | None listed | None, ever |
Klaviyo pricing as listed on the Shopify App Store, July 2026. Kelso pricing is current and listed in full on the pricing page.
Why merchants switch
What Klaviyo reviewers report
These are paraphrased from dated, public one-star reviews on Klaviyo's Shopify App Store review page. They are individual merchant reports, not our claims about every merchant's experience.
The Kelso difference
What Kelso does differently
- Two-path restock detection. The inventory webhook fires first and a scheduled reconciliation poll runs behind it, so a dropped webhook cannot become a false alert or a missed one.
- A full send audit log. Every alert is accounted for: queued, sent, delivered, clicked.
- Flat, predictable send-based pricing. Your bill is set by how many alert emails go out, not by how many contacts sit in your account, so a growing subscriber list never quietly pushes you into a higher tier.
- A free plan that never paywalls subscriber capture. Only send volume is gated, and that is written down.
- Human support that replies in hours. The promise is published on our support page.
A fair look back
Where Klaviyo may still fit you
A fair comparison cuts both ways. Based on the same public pricing page and listing:
- Klaviyo is the category leader for a reason. It holds a 4.7 star rating across 2,919 reviews on its Shopify listing, and reviewers consistently praise its segmentation, automation, and analytics.
- Klaviyo ships its own native back in stock flow for free, inside its platform, if you are already a Klaviyo customer. Kelso is not trying to out-build that flow. Our differentiator is a dedicated, theme-matched product-page widget and a focused send pipeline built only for restock alerts, not a reason to avoid Klaviyo if you already run it for the rest of your marketing.
- If you want one platform for email, SMS, flows, and analytics across your whole store, Klaviyo is a genuinely strong, full-featured choice and Kelso is not trying to replace it.
- Klaviyo pricing is set by active profile count, which means a store with a large contact list pays more even in months with light send volume. If restock alerts are one flow among many you run, that tradeoff may still be worth it for the rest of the platform.
Switching takes a CSV export
Export your waitlist from Klaviyo, upload it into Kelso, and your subscribers carry over. Stuck on the export? Email us and a person will help.
Free to install. Free migration from Klaviyo, we'll help by hand.
Founding 50
The first 50 stores to install lock today's price for as long as they stay subscribed. No countdown, the count is real.
Coming from Klaviyo's back in stock flow? Switching is a CSV upload. See how migrating to Kelso works.
New store still deciding? Start on Kelso's free plan (50 alert sends a month, unlimited subscribers captured). Want to see how the dedicated back in stock apps compare on price? Read the back in stock app pricing breakdown.