Klaviyo vs Mailchimp vs HubSpot vs Constant Contact: how the email platforms differ

Before you choose an email platform, check four things: which plan includes automation, how contacts are billed, how the platform connects to your store or CRM, and what you can export when you leave. Below, Klaviyo, Mailchimp, HubSpot and Constant Contact are compared with Omnisend and Shopify Email (now called Shopify Messaging), using each vendor’s own pages.

By Donnie Strompf. Updated October 2026.

I’m Donnie Strompf and I’ve done SEO since 2008. I run an agency, so read this as advice to a buyer. It uses vendor documentation, not hands-on testing, and it does not rank the platforms. Ask any provider, including us, which platform it works in and who owns the account.

Key takeaways

  • HubSpot requires Marketing Hub Professional or Enterprise for workflows, and Mailchimp’s pricing table lists no automation flows on Free, though its feature page mentions one email automation.
  • Klaviyo bills reachable contacts, HubSpot bills marketing contacts, and Omnisend bills subscribers plus non-subscribers who received automated messages.
  • HubSpot syncs Shopify orders one way only, and Klaviyo tells you to switch off Shopify’s own abandoned checkout emails.
  • Every platform here exports contacts to a spreadsheet file. Klaviyo and Mailchimp say the export leaves out history, and HubSpot says contact activities need a separate export.
  • Plan prices change often. Price your own list size on each vendor’s pricing page on the day you buy.

Where do these facts come from?

Every row comes from a vendor’s own help, plan or export page, read on October 15, 2026. Where a page shows an update date, it is named below. Plan prices are not quoted. Their pricing pages are linked: Klaviyo, Mailchimp, HubSpot Marketing Hub, Constant Contact, Omnisend and Shopify Messaging.

Vendor pages sometimes disagree with themselves. Omnisend’s pricing page shows 6,000 emails a month on the Standard plan card but “12× your list size” in its comparison table. Treat the live plan page as the authority when you buy.

How do their automation builders differ?

Klaviyo’s flows can start from a list, a segment, an event such as placing an order, a date property, a price drop or low inventory. A conditional split can branch into up to 20 paths (Klaviyo Help Center, updated October 7, 2026).

Mailchimp’s plan table lists marketing automation flows as not included on Free, up to 4 flow steps on Essentials, and up to 200 flows on Standard and Premium (Mailchimp pricing page). Its automation feature page says “The Free plan only allows you to set up a single email automation,” so the two pages differ. HubSpot’s knowledge base says a Professional or Enterprise subscription “is required to use workflows” (HubSpot, updated August 3, 2026).

PlatformWhat starts an automationPlan gate
KlaviyoList, segment, event, date, price dropNot stated on the flows page
MailchimpAutomation flowsFree: pages differ; Essentials 4 steps
HubSpotWorkflowsProfessional or Enterprise
Constant ContactAutomation templatesLite 1; Standard 3; Premium custom
OmnisendCart and order messagesListed on every tier
Shopify MessagingWelcome, winback, upsell templatesBasic, Grow, Advanced, Plus

Constant Contact’s pricing page gives Lite one automation template and Standard three. Premium adds unlimited templates plus custom automations. Omnisend lists email automation on every tier, with cart abandonment and order confirmations. Shopify says its tool builds workflows from a trigger plus conditions and wait steps (Shopify).

If you run a service business, check whether your booking or scheduling tool can send the platform a signal when a booking is made or a visit is completed.

How do their segments differ?

Klaviyo says its segments update quickly and can target what someone has done or not done (Klaviyo Help Center, updated January 20, 2026). HubSpot has active lists that update themselves and static lists that do not, and its article lists both under all products and plans (HubSpot, updated September 29, 2026).

PlatformSegments built onLimit
KlaviyoActions taken or not takenNone stated
MailchimpSaved segments, tags, groupsPredictive on Standard, Premium
HubSpotActive and static listsSame on all plans
Constant ContactContact info, lists, email, SMS, shopping1, 10 or unlimited by plan
OmnisendSegments and tagsUnlimited on every tier
Shopify MessagingCustomer lists or segmentsNone stated

Constant Contact is the one to read closely. Its knowledge base says “the number of segments you can create depends on your email plan” (Constant Contact, updated May 1, 2026), and its pricing page puts the figure at 1 custom segment on Lite, 10 on Standard and unlimited on Premium.

Which platform connects best to an online store?

Each Shopify connection syncs different data, so compare the rows below. If your store runs on another platform, check each vendor’s integration list for it before comparing anything else.

PlatformShopify data documentedWatch for
KlaviyoCustomers; cart, checkout, order eventsTurn off Shopify’s abandoned checkout emails
MailchimpCustomer and order data, cart eventsNo product catalog sync described
HubSpotContacts, companies, products; orders one wayCompany sync needs Shopify Plus
Constant ContactListed among 300+ integrationsEcommerce templates on Premium
OmnisendContacts, products, ordersOne store per account
Shopify MessagingBuilt into Shopify adminNetwork Intelligence setting required

The sources: Klaviyo’s Shopify data article (updated November 18, 2025), Mailchimp’s Shopify syncing page, HubSpot’s Shopify data sync article (updated June 22, 2026), Omnisend’s Shopify integration article (updated May 21, 2026) and Shopify’s help page.

Check sync delays and refund handling before you build an automation. Omnisend says the first import takes about an hour for most stores and up to 24 hours for a full history. HubSpot says Shopify product variants cannot sync. Klaviyo says it only receives events from fully refunded orders, so its revenue totals can differ from Shopify’s.

How do list limits and billing work?

Each platform counts a different group of people as billable, so read the counting rule before you compare plan prices.

PlatformCounted for billingFree tier or send cap
KlaviyoReachable contactsSend capacity set by tier
MailchimpContact-count tierFree: 250 contacts, 500 sends a month
HubSpotMarketing contacts onlyOne extra contact raises the tier
Constant ContactContacts and sendsSends capped at 10x to 24x contacts
OmnisendSubscribers, plus non-subscribers sent automationsFree: 250 contacts, 500 emails a month
Shopify MessagingEmail volume10,000 emails a month free

Klaviyo’s pricing page says “Billing is based on reachable contacts, while unsubscribed and suppressed contacts do not count” (Klaviyo, October 2, 2026). HubSpot bills marketing contacts, and “if you exceed your current tier by even one marketing contact, you’ll be upgraded to the next contact tier” and stay there until renewal (HubSpot, updated August 14, 2026).

Going over a cap behaves differently too. Constant Contact’s pricing FAQ says emails still go out when you pass the limit, with an overage fee per extra send. Mailchimp says its free plan sending “will be paused” at the limit, while paid plans take overages. Shopify’s page says the first 10,000 emails a month are free, then you pay per email.

How easy is it to leave each platform?

Export a sample contact list before you commit. Each help page below describes a contact export. Whether campaign history and performance data come with it is a separate question to ask.

PlatformFormatWho can run itLeft out or limited
KlaviyoCSVOwner, Admin, AnalystEvent data, messages received
MailchimpCSVOwners and AdminsOpen and click rates
HubSpotCSV or Excel filesExport permissionCalls and notes
Constant ContactCSV or ExcelNot statedPermission status, unless enabled
OmnisendCSVOwner, Admin, AnalystNo scheduled exports
ShopifyCSVNot stated15 MB file limit

The sources: Klaviyo (updated July 7, 2025), Mailchimp, HubSpot (updated April 2, 2026), Constant Contact (updated August 31, 2026), Omnisend and Shopify.

HubSpot also publishes an account-wide export article (updated August 25, 2026) that covers templates as HTML files and marketing email analytics. Constant Contact’s export leaves out permission status unless Advanced Email Permissions is on, which matters if you must show consent.

Ownership matters as much as export. Open the account under your own business login, as owner, and add any agency as a user. Who owns your website and marketing accounts walks through that pattern for Google tools, and the same logic applies to an email platform. If you want an agency to run it, see our email marketing services and our guide to how much digital marketing costs for a small business.

What should you check before you switch platforms?

Start with the export itself, because each vendor limits it differently. Klaviyo keeps finished exports under Settings for 30 days, and a list export carries up to 700 columns at once (Klaviyo Help Center). Mailchimp keeps an export available for 30 days, may deliver it as a ZIP with one CSV per contact type, and exports archived contacts separately (Mailchimp).

HubSpot allows up to 300 exports in a rolling 24 hours, zips CSV files over 2 MB, and expires download links after 30 days (HubSpot, updated April 2, 2026). Omnisend does not support scheduled exports, so each one is manual (Omnisend). Shopify emails the file to you when you export more than 50 customers (Shopify).

Next, check which contacts the file contains. Mailchimp’s export can include unsubscribed and cleaned contacts, and Klaviyo says an all-profiles segment export includes profiles “regardless of subscription status.” Keep the unsubscribed list and move it with the rest, so you do not email people who opted out. Constant Contact notes that exporting does not remove contacts from your account, so treat the export as a backup first.

Plan to rebuild automations by hand. HubSpot’s account export article says a workflow export is a spreadsheet of workflow lists plus images of each workflow, without performance data or history. None of the other help pages above describes a way to carry flows to a competitor, so budget time to rebuild your welcome and cart messages and to test them on a small segment.

How do you choose between them?

The table names what to check for each situation and picks no winner.

If this describes youCheck first
You sell on ShopifyThe store table’s “Watch for” column
Your records live in HubSpotWhether you need Professional for workflows
Your list is smallFree-tier caps on contacts and sends
You fear surprise billsWhat happens when you pass a cap
You may switch laterA test export first

Your platform also needs a way to collect subscribers. What to expect from SEO explains how search traffic can bring people to your site.

Before you sign up, run this checklist with the vendor or your agency:

  1. Which of my contacts will count toward the bill, and how is that written on the plan page?
  2. Which plan includes the automation I need, and what does it cost to move up one level?
  3. What does the Shopify or CRM connection sync, and what does it leave out?
  4. Who is the owner of the account, and is it my business?
  5. Can I run a full contact export today and open the file?

Related reading

Next step

If you want help with email, or with how your business appears in search and AI answers, the free AI-visibility audit comes first, then a 15-minute call. Our email marketing services page explains what email work involves, and pricing lists the published range.

FAQ

Which email platform costs the least for a small business?

It depends on your list size, send volume and extras such as text messages. Each vendor counts and caps differently, so enter the same contact number into every pricing page on the same day. Add any SMS charge and any overage rule, then compare the totals instead of the headline plan names.

Can I move my list to a new platform without losing consent records?

You can move the addresses, but check the consent fields. Klaviyo’s export carries consent status and timestamp, and Mailchimp’s can carry marketing permissions and opt-in times. Constant Contact omits permission status unless it was enabled before the export. Open a sample file and confirm those columns exist before you cancel anything.

Do I need Klaviyo if I run a service business?

Not necessarily. Any platform can send newsletters and reminders. What matters is whether your booking, scheduling or CRM tool can pass events to it, such as a booking made or a visit completed. If it cannot, a simpler platform with a working connection beats a larger one without.

Do I need text messaging in the same platform?

Text messaging is billed apart from email on the platforms that offer it. Klaviyo bills text separately from its email plan, Omnisend charges per message, and Shopify offers SMS only in select countries. Decide whether you need texting now, because it changes every comparison above.

Is Shopify’s built-in tool enough, or should I add a separate platform?

Start with what you need to send. Shopify’s page describes templates and workflows inside the admin, billed by email volume. A separate platform adds its own builders and a second login. Test one welcome or cart reminder flow in each before you move the whole list.

Have these platforms changed rules or names recently?

Several have. Mailchimp renamed its automation builder to Marketing Automation Flows effective June 2025 (Mailchimp pricing page), and Klaviyo’s billing changes took effect February 18, 2025 (Klaviyo Help Center). Shopify Email is now Shopify Messaging. Re-read the plan page before you buy.

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