Brevo vs Customer.io

How this comparison was built

The prices and plan limits on this page come from each vendor's public pricing page, as read on 7 October 2026. Where a price depends on volume, the tables name the band it applies to. Feature claims are limited to what each vendor's pricing page or product description states. Anything a page does not state is left out rather than guessed, so the gaps you find in this comparison are gaps in the public information, not gaps in the analysis.

Who each tool is built for

Brevo is organised around the marketing or operations team. Campaign builders, contact lists, SMS and transactional sending sit in one interface, so a small team can run a product newsletter, a trial onboarding sequence and password-reset mail without moving between separate products. For an early-stage SaaS company, that consolidation usually matters more than deep event logic, because the first questions tend to be who is subscribed, what was sent, and whether the messages reached the inbox.

Customer.io is built around people as profiles. Each profile carries identity, attributes and a history of custom events, and journeys branch on that state. The growth lead and the engineer work from the same event model. That pays off when onboarding depends on which features a user has actually activated, or when a failed payment should change which message goes out next. The cost of that precision is that someone has to own the event schema from the start.

Comparison at a glance

Read the table as a set of trade-offs rather than a ranking. Brevo wins on consolidation and on the entry price for a team that sends newsletters and transactional mail. Customer.io wins on how precisely a message can follow a person's behaviour, and it asks more of the team in return.

Deliverability groundwork that applies to both

Neither platform decides inbox placement by itself. Most of what determines it is set up before the first send, and it applies whichever tool you choose.

• Authenticate the sending domain. Publish SPF and DKIM for every platform you send from, and set a DMARC policy in DNS. This is a DNS task you own, not a feature you purchase, and it should be finished before the first production send on either platform.
• Separate transactional from marketing mail. Receipts, invoices and password resets should not share a sending reputation with a promotional newsletter. Decide early whether they use one sending domain or subdomains, and document the choice for each tool.
• Clean addresses before import. Address validation is a separate step with its own cost. The plan descriptions used for this page do not list it as an included feature on either platform, so budget it on its own line.
• Honour suppression everywhere. Unsubscribes, spam complaints and hard bounces must stop future sends in every system that holds the address. A list that keeps mailing bounced addresses is one of the quickest ways to lose inbox placement.
• Watch the failure signals. Bounce, complaint and unsubscribe rates by campaign tell you more about list health than open rates do. Check that the platform you choose reports these per send, so a problem can be traced to a specific list, template or sequence.

The two tools differ mainly in where the suppression logic lives and how much of it you can see. A simpler default is faster to live with, but it is harder to audit when something goes wrong, so ask each vendor to show you how a complaint on one message is handled across later sends.

Brevo in detail

Brevo's clearest advantage for a SaaS team is breadth at a low entry price. The free plan allows 300 email sends a day and storage for up to 100,000 contacts, which is enough to build a first list and send early announcements before any money changes hands. The paid Starter plan begins at $9 a month for 5,000 emails a month and has no daily sending limit.

Standard, at $18 a month from the same 5,000-email starting band, adds automation, A/B testing and advanced reports. For most SaaS teams this is the plan that matters, because welcome sequences, trial reminders and re-engagement messages all depend on automation. Professional, at $499 a month for 150,000 to 10 million monthly sends and up to 2 million contacts, is the tier for high-volume senders. The pricing page shows $449.08 a month on the yearly option.

Where Brevo falls short. It is less strong on event-native journeys. A flow can react to a campaign click or a contact property well enough, but a SaaS team that wants to branch on dozens of product events, merge identities from several systems and keep a full event history per person will reach the limits of the contact model sooner. Read the pricing page carefully on how contacts and sends are counted, because the two drive different parts of the bill and add-ons change the total.

Current plan terms are on the Brevo pricing page.

Customer.io in detail

Customer.io's advantage for SaaS is precision about behaviour. Profiles hold identity merges, attributes and custom events, and the workflow builder can branch on any of them. A trial user who has connected an integration can receive a different sequence from one who has not, and a user who stops using a core feature can enter a re-engagement path without a manually maintained segment.

The Essentials plan is listed at $100 a month and includes AI Agent core skills, the visual workflow builder, email and community support, and basic data integrations. The profile bands on the same pricing page run from $145 a month at 10,000 profiles, to $235 at 20,000, $325 at 30,000, $415 at 40,000, and $505 a month at 50,000 or more. Those bands are billed monthly. Premium, listed at $1,000 a month, is priced on custom profile volume and adds elevated AI Agent limits and premium support.

Where Customer.io falls short. Event discipline is the price of admission. Every event name, property and identity key needs an owner, and a messy schema shows up as a broken journey rather than a clear error message. The profile-based bill also rises with the audience, so a team with a large base of free users who rarely receive email may pay for profiles it does not mail often. That is a reason to model the profile count carefully before committing.

The Startup Program is worth a look for eligible early-stage companies. Companies that have raised under $10M can receive 12 months free, and the pricing page sets out the eligibility rules. Current terms for every plan are on the Customer.io pricing page.

What the cost looks like at three list sizes

Brevo bills on monthly sending volume, and Customer.io bills on profiles. The table below sets the plan or band each vendor's pricing points to at three audience sizes. It cannot show an exact bill, because that depends on how many emails each audience receives and on any add-ons you buy.

Reading the table. The arithmetic below uses only the monthly prices shown above, multiplied out over twelve months.

• At the smallest band, the gap runs the other way from the headline prices. Brevo Standard at $18 a month comes to $216 across twelve months. Customer.io Essentials at 10,000 profiles, at $145 a month, comes to $1,740 across twelve months.
• At 20,000 profiles, Customer.io Essentials at $235 a month comes to $2,820 across twelve months. Brevo Professional at $499 a month comes to $5,988, or $5,388.96 on the yearly option shown on the pricing page. That comparison holds only if the Customer.io account also sends the same 150,000 emails a month, and the Customer.io pricing page should be read for whether email volume changes the bill.
• At 50,000 profiles, Brevo Professional stays at $499 a month, as long as monthly sends stay in the 150,000 to 10 million band and the contact count stays within 2 million. Customer.io's 50k-and-above band is listed from $505 a month.

The practical lesson is that the cheaper tool depends on the shape of your audience. A large list with light sending can cost less on Customer.io's profile bands than a high-volume sender costs on Brevo's Professional plan, and a small list that sends a lot can cost much less on Brevo.

Which one fits which decision

The table below turns the trade-offs into decisions. Each row names the pick and the reason, so you can see which requirement is doing the work.

How to choose

1. List the three emails that matter most to the business, usually welcome, onboarding and either billing recovery or re-engagement. Count how many branches each one needs and what those branches depend on.
2. If none of those emails branches on product events or individual attributes, Brevo's contact model is probably enough, and the lower monthly price applies.
3. If at least one email branches on three or more events or profile attributes, model Customer.io's band for your profile count and compare it with the Brevo plan for your monthly volume.
4. Price both tools at the audience size you expect in twelve months, not the list you have today. Plan costs change faster with growth than with the current list.
5. Before committing, set up authentication, suppression and address hygiene in a test environment on each tool, and read the vendor's own documentation for each step.

Setup and migration checklist

Moving from one tool to the other is mostly data work. Plan for weeks rather than days, and keep the old system sending until the new one has matched its counts.

When migrating, treat suppression history as the first thing to move, before any contacts are imported. An address that unsubscribed or complained in the old system should never be loaded as active in the new one.

Where each one wins

A pilot that settles the choice

A short pilot will show more than any comparison page. Run the same workflow in both tools on real users, and judge each one on the points below.

• Run the same onboarding sequence in both tools for two weeks on a segment of real users, and confirm that triggers and exit conditions behave the same way in each.
• Trigger one unsubscribe and one hard bounce, and confirm that the address stops receiving mail in both systems.
• Send a test user through the key product events, and confirm that the events appear on the profile with the expected timestamps and properties.
• Bill the pilot at the next audience band, using the plan prices on each vendor's pricing page, and compare the result with your current spend.

Related reading

Continue with the SaaS email service guide, the deliverability guide, the alternatives hub, and the Stripe-focused review. For more head-to-head pages, see the comparison index.

Frequently asked questions