Sendlane vs Klaviyo: An Honest Comparison

Klaviyo is the safer pick for most Shopify brands: a free tier, a published starting price and 350+ app integrations. Sendlane is worth a serious look if you carry a large list, send a few campaigns a month, and want 24/7 chat support and a 60-day trial included rather than sold as extras.

Do you have a large list and a low send frequency?

The whole Sendlane pitch rests on one billing choice. Its pricing page says “Unlimited Contacts – Pay for sends, not profiles” and “Our plans are based on what you send, not on the number of contacts in your account” (Sendlane pricing page, 4 October 2026). Every plan includes “Unlimited Profiles”. You pay for email volume, and a dormant profile costs nothing until you email it.

Klaviyo does the opposite. “Your monthly profile tier is based on the total number of billable profiles in your account at the time of billing”, and “Any profile, regardless of consent status, that can be emailed through Klaviyo is considered an active profile” (Klaviyo help centre, 25 March 2026). Pricing “starts at $60 per month based on active profiles”, with a free tier for accounts under 250 active profiles and 500 monthly sends (Klaviyo product page, 4 October 2026). Profile growth moves you up a tier at the next billing cycle, and heavy email usage can auto-upgrade you as well.

So the arithmetic is simple to set up and impossible to finish from public pages. A brand with 80,000 emailable profiles that sends twice a month pays Klaviyo for 80,000 profiles and Sendlane for 160,000 sends. A brand with 10,000 profiles sending daily pays Klaviyo for 10,000 profiles and Sendlane for 300,000 sends. Which is cheaper depends on the two rate cards, and neither rendered: Sendlane’s send-volume prices and Klaviyo’s tier table are both missing from the pages we fetched, so we state neither. Sendlane’s own landing page says brands that “Replace Klaviyo, Postscript & More” are “saving up to 30%” (Sendlane landing page, 4 October 2026), which is Sendlane’s claim and will be true for some list shapes and false for others.

The rule of thumb that survives the missing numbers: the bigger the gap between your emailable profiles and your monthly sends, the better Sendlane’s model looks. Ask both vendors for a quote at your actual profile count and send volume, same month, same numbers.

How much do you need SMS and support bundled in?

Sendlane’s second argument is the bundle. Its homepage line is “One login, one bill, one platform, one data hub, one team to support it all”, and every plan includes “24/7/365 chat support”, “Deep Data Integration to Shopify” and proactive deliverability monitoring (Sendlane pricing page, 4 October 2026). SMS is native and sold in credits: “SMS available starting at $0.009 per credit inclusive of carrier fees”, with a “Monthly Activation: $10” fee and credit packs at 250 for $6.25, 500 for $11, 1,000 for $21, 2,500 for $50, 5,000 for $90 and 10,000 for $175 (Sendlane pricing page, 4 October 2026). Note that the smallest pack works out at 2.5 cents a credit, so the $0.009 rate is a high-volume figure, and the $10 activation applies monthly whether you send or not.

Klaviyo sells SMS as a separate Mobile Messaging subscription. From 13 July 2026 it moved “from credits to per-message, dollar-based rates”, priced as “Rate x Recipients x Message segments = Total cost”, with carrier fees bundled into the plan rate (Klaviyo help centre, 4 October 2026). Per-country rates are shown in-product only, so we cannot put a US number beside Sendlane’s.

On support, Klaviyo’s free tier includes email support for the first 60 days only (Klaviyo help centre, 4 October 2026); paid-tier support is not spelled out on the pages we fetched. Sendlane’s “24/7/365 chat support” on every plan is a clearer promise, and for a lean team sending at odd hours it is a real advantage.

On trials, Sendlane offers 60 days limited to 100 contacts and 500 email sends, with no free plan (Sendlane pricing page, 4 October 2026). Klaviyo has no time-limited trial because the free tier is permanent at 250 profiles and 500 sends. Both let you test a real flow before paying; only Klaviyo lets you keep running for free.

Are you leaving Klaviyo to save money, or to simplify?

Sendlane’s landing page offers “Move now, pay later: you won’t pay a penny until you’re fully onboarded and successfully sending” (Sendlane landing page, 4 October 2026). That removes the double-paying period that normally kills a migration. Its homepage adds “50+ pre-built funnels” and “Smarter Email & SMS”. For a brand running a handful of core flows, a reviews app and a loyalty app, that may be all you need.

Klaviyo’s counter is breadth. “Integrate with 350+ apps”, “One platform for every customer journey” and “Let AI do the optimizing for you” are the product page’s lines, and it reports “205,000+ relationship-driven brands across 100 countries” (Klaviyo product page, 4 October 2026). Sendlane does not publish an integration count on the pages we fetched. Before you move, list every app that pushes events into Klaviyo today and confirm each one has a Sendlane equivalent. That list, not the rate card, is usually what decides it.

Sendlane’s /compare/klaviyo page returned homepage content when we fetched it, so none of its claims are verified here.

The honest summary: Sendlane wins on billing logic for big, quiet lists, on support promise, on trial length and on migration terms. Klaviyo wins on free entry, published starting price, integration count and the likelihood that your other apps already connect to it. In the retention email programmes we run, [BMO NUMBER: insert the share of flow revenue that came from app-triggered events such as reviews or loyalty, with account count and window] is the figure that tells a brand how much integration depth is worth to it. If the comparison that interests you is Klaviyo against a cheaper self-serve ESP, read Klaviyo vs ActiveCampaign; if you are deciding whether to leave Shopify’s built-in tool at all, start with Klaviyo vs Shopify Email.

In-body table: Sendlane vs Klaviyo at a glance (vendor pages, 4 October 2026)