Userlist vs Customer.io: which one should run lifecycle email for a SaaS product?

Short answer

For most product teams, Customer.io Essentials is the better buy: it was the cheaper plan at every list size we could price ($145 a month at 10,000 profiles against $149 for Userlist Basic), and A/B testing, push, in-app and WhatsApp come with the entry plan. Choose Userlist when you sell to companies rather than individuals, want company segments and company-triggered campaigns ready to use, and would rather have a 60-minute roadmapping session than a self-serve builder. Both prices were read from Userlist's pricing page and Customer.io's pricing page on 7 October 2026, with monthly billing selected.

Price at four list sizes

Userlist's figures at 10,000, 18,000 and 32,000 users are slider readouts; its page also has an annual toggle labelled "Annual — Save 20%", which we did not price. Customer.io's slider read $145, $235, $325 and $415 at 10,000, 20,000, 30,000 and 40,000 profiles on Essentials billed monthly, and "$505+" at 50,000 or more, where the page suggests Premium instead. The 18,000 and 32,000 figures in the table are not slider readouts: they apply the page's $0.009 per additional profile to the $100 base, the rule that reproduces its 10,000 and 20,000 readouts. We read nothing from Userlist above 32,000 users, and its page says rates fall as a list grows, so no price is extrapolated past that point.

What each plan includes

Userlist's Basic card describes "marketing and lifecycle email, plus in-app messages and notifications to your team" and says it now includes company accounts. The bullets add 500,000 emails a month, segments for users and companies, broadcasts, visual workflows, transactional email and a 60-minute roadmapping session for new accounts. Professional repeats all of that and adds A/B split testing, conversion goals, advanced workflow features, advanced integrations and group training for your team. Enterprise has no price, only "Let's talk", with custom message limits, a dedicated account manager and monthly review calls. The feature table also caps Basic at 20 custom properties, 20 custom events and 5 team seats, against 50, unlimited and 10 on Professional.

Customer.io's Essentials card lists 5k profiles counted as people plus objects, an AI Agent with core execution skills, one million emails a month, two object types, the visual workflow builder, email and community support and basic data integrations. Its comparison table adds what the card leaves out: transactional email, A/B and multivariate testing, conversion tracking, unlimited push and in-app messages, native WhatsApp, unlimited webhooks and unlimited user seats are all included on Essentials, while SMS volume is custom. Not included on Essentials are chat support, onboarding support, managed deliverability and custom role-based permissions. Premium starts at $1,000 a month billed yearly, which is $12,000 over a year, with custom volume, ten object types, 90-day onboarding support and HIPAA compliance listed.

Where the two products differ

A/B testing sits behind the expensive Userlist plan

At 10,000 users, Userlist Professional is $349 and Customer.io Essentials is $145. That gap is $204 a month, or 12 × $204 = $2,448 a year. If split testing a subject line or a trial-ending email is something you do weekly, that gap is the real price of the Userlist feature set, because Userlist lists A/B split testing and conversion goals only on Professional. Customer.io's table shows both included from Essentials. Professional also brings advanced workflow features and group training, so the comparison is not purely about testing, but a team that only wants to test should not pay $204 for it.

Companies: built-in accounts or objects

This is the strongest case for Userlist. Its feature table lists company profiles with an activity feed, company segments, company-triggered campaigns and many-to-many relationships between users and companies, and its Basic card says company accounts are included. With Customer.io you model the same thing with objects: Essentials allows two object types, Premium ten, and every object is a profile billed at $0.009 beyond the plan size. A product with 6,000 users in 1,200 accounts therefore carries 7,200 profiles in Customer.io. The sum is $100 + 2,200 × $0.009 = $119.80 a month. Userlist's page says it counts "all users" and does not say whether company records add to that total, so ask before you size the plan.

Event and property limits

A SaaS product that tracks trial_started, invoice_failed, seat_added, export_created and a dozen more events can hit Userlist Basic's limit of 20 custom events and 20 custom properties sooner than expected. Professional removes the event cap and raises properties to 50. We did not find a comparable cap on Customer.io's pricing page, which is not the same as there being none, so check its documentation before a large tracking plan.

What happens above the email allowance

Userlist's billing documentation says every plan carries a monthly message allowance of five times your tracked users with a floor of 500,000, and charges $1 per 1,000 messages above it. Take 18,000 users: 5 × 18,000 is 90,000, so the 500,000 floor applies. Send 720,000 messages in a month, for example 40 per user, and you pay for 220,000 extra, which is 220 × $1 = $220 on top of the $229 plan. Customer.io Essentials includes one million emails and charges $0.12 per additional 1,000, so the same 720,000 costs nothing extra. At 1,200,000 emails the sum is 200 × $0.12 = $24 above the plan price. Heavy notification senders should run this sum before they choose; a product that sends a handful of lifecycle emails per user will sit far below both limits.

Channels

Userlist's pages describe email, in-app messages and internal notifications to your own team, and we found no SMS or push in its plan descriptions. Customer.io lists email, push, in-app, native WhatsApp and LINE, with SMS volume custom. If the product is a web app with email as the main channel, that list is capacity you may never use; if you run a mobile app that needs push with an email fallback, it decides the question.

Setup help and support

Userlist includes a 60-minute roadmapping session on Basic to plan integration, segments and workflows, and group training on Professional. Customer.io Essentials gives email and community support, and puts chat support and onboarding on Premium. Neither vendor's page says how long a typical integration takes, so the difference is the structure around the first month, not a promise about speed.

How each one counts users

Userlist looks at the previous 30 days and bills on the high-water mark of users in the account, counting everyone it stores rather than only active users, and you can remove users through the API to lower the figure. Customer.io works the same way in spirit: according to its billing documentation, a profile that exists at any point in the billing period counts even if you delete it, a profile deleted and re-added in the same period counts twice, and test, dev and sandbox workspaces are included in the total. Import a list once, remove test data before the period starts, and your bill follows the real list.

Free trials and startup offers

Userlist offers a 14-day trial on all plans and asks for card details upfront. Companies that have raised less than half a million dollars in total and are new to Userlist can ask for 50% off for the first 12 months. Half of the $149 Basic readout at 10,000 users is $74.50 a month, or 12 × $74.50 = $894 over the year. Customer.io has no free plan but gives companies that raised under $10 million a full year free through its Startup Program. At the $145 readout for 10,000 profiles, that is worth 12 × $145 = $1,740. If you qualify for either, the first-year price is a different calculation from the table above.

Choose Userlist if…

• your customers are companies, and campaigns should trigger on company-level behaviour with company segments from day one;
• you want a guided start: a roadmapping session on Basic and group training on Professional;
• your list is around 10,000 users, where the Basic plan is within $4 of the Essentials readout;
• you send fewer than 500,000 messages a month and track fewer than 20 distinct events.

Choose Customer.io if…

• you want A/B testing and conversion tracking without paying the $204 gap to a Professional-level plan;
• your product has a mobile app, or you may need push, WhatsApp or SMS next to email;
• you send more than half a million emails a month, where its $0.12 per 1,000 beats $1 per 1,000;
• your company raised under $10 million and can claim 12 free months.

Moving from one to the other

Export users with their attributes and decide event names before you touch a workflow, because both tools trigger on events your application sends. Rebuild segments and workflows by hand; we found no automatic migration of workflows between the two. Userlist's feature table lists personalization with Liquid, so check each template's merge syntax after you copy it into the new tool. Run the old and new system side by side for one billing period with a small group, and authenticate your sending domain in the new tool before the first send.

When leaving Userlist, export everything you want to keep first: its billing documentation says it deletes the account with its users, segments, workflows and message history shortly after cancellation takes effect, and that the deletion cannot be undone. When arriving at Customer.io, count profiles before you import, since people and objects both bill. For other shortlists, see Customer.io vs Drip and Customer.io vs Loops; for the audience view, read the B2B SaaS email guide, the onboarding guide and our note on SaaS onboarding sequences, or return to the comparison hub.

FAQ

Which is cheaper, Userlist or Customer.io?

Customer.io Essentials, at every size we priced. At 10,000 the readouts are $145 and $149, at 18,000 the difference is $12 and at 32,000 it is $26. Against Professional, the plan that carries A/B testing, the gap at 10,000 users is $204 a month.

Does either have a free plan?

Neither lists one. Userlist offers a 14-day trial with card details upfront and 50% off for 12 months to qualifying new accounts that raised under half a million dollars. Customer.io gives eligible companies that raised under $10 million 12 months free through its Startup Program.

Do companies count toward my bill?

At Customer.io, yes: profiles include objects, and objects are billed at $0.009 each above the plan size. Userlist's pricing page says it counts all users but does not say whether company records add to that number, so ask support before choosing a size.

Can I move my data out of Userlist later?

You can export it, and you should do so before cancelling. Userlist's billing documentation says account data, including message history, is deleted permanently after cancellation and cannot be restored.