Mailchimp vs Brevo

What the billing models mean for a SaaS audience

Mailchimp asks the team to treat the audience as a priced asset. Its Free, Essentials, Standard and Premium marketing tiers use contact stops, and the paid plans list monthly sends as a multiple of contacts: 10× on Essentials, 12× on Standard and 15× on Premium. A 5,000-contact Standard audience therefore has a stated allowance of up to 60,000 emails per month. This can be predictable for a team that sends a regular cadence, but it also makes old records expensive. An unsubscribed contact does not become free merely because the person cannot receive a campaign; archive or remove contacts that no longer have a purpose.

Brevo asks a different question: how many marketing emails will be sent in the month? Its Starter and Standard prices step up with selected volume, while contact storage is a separate constraint. The Free plan lists up to 100,000 stored contacts and 300 sends per day. Paid points in the published pricing view pair 5,000 sends with up to 500 contacts, 10,000 with up to 1,500, and 15,000 with up to 2,500; from 20,000 through 100,000 sends, the page lists up to 500,000 contacts. That pairing makes the volume slider useful for a quiet large list only when the selected tier includes the storage the business needs.

For a B2B SaaS, the decision should start with two inventories. First, count every person the product may need to address, including dormant users, unsubscribed users kept for suppression history, and contacts shared across workspaces. Second, count the actual monthly sends: onboarding, product notices, newsletters, reactivation, and any operational messages that truly belong in the marketing service. A large audience with two campaigns can favour Brevo. A small audience with several weekly journeys can favour Mailchimp if its contact tier contains the send allowance and the team values its editor and integrations.

• Mailchimp: contacts are the primary billing lever; sends are a multiple of that contact count.
• Brevo: selected monthly email volume is the primary billing lever; storage limits vary by volume point and plan.
• In both systems, consent, suppression, archiving and sender authentication are operating work, not optional cleanup.

Worked scenario: a large but quiet B2B SaaS list

Imagine a SaaS with 40,000 stored contacts. Only 5% are active each month, so the marketing team sends one product newsletter to 2,000 people and one reactivation message to the same 2,000. The send arithmetic is 2,000 × 2 = 4,000 emails per month. The other 38,000 contacts stay stored for suppression, future reactivation or account history.

Brevo’s Free plan lists 300 sends per day. Over a 30-day month that is 300 × 30 = 9,000 possible daily sends, which is above this scenario’s 4,000 monthly emails. Its Free plan also lists storage for up to 100,000 contacts. On those stated limits, the scenario can fit at $0 per month before any need for paid automation or removal of the Brevo footer. If the team needs a paid plan, Brevo lists Starter at $9/month for 5,000 emails/month; $9 × 12 = $108 per year, and the 4,000-send requirement remains under that selected volume.

Mailchimp’s Free plan lists only 250 contacts, so 40,000 stored contacts cannot use that entry point. The contact count also exceeds the published 0–500, 2,501–5,000 and 5,001–10,000 anchors; the exact larger audience price is pricing on request. The key result is not a guessed Mailchimp total. The arithmetic shows why a contact-priced system is structurally disadvantaged for a large, quiet database: the bill follows 40,000 stored contacts even when only 4,000 emails leave the system.

The recommendation for this scenario is Brevo if the team is comfortable with the Free plan’s automation and branding limits. If the list must run advanced journeys, compare the exact Brevo volume and contact-storage point with a Mailchimp quote. Keep the 38,000 quiet contacts only when there is a retention reason; deleting needless records can change either vendor’s economics and reduce privacy work.

• Audience: 40,000 stored contacts; active recipients: 2,000.
• Send arithmetic: 2,000 × 1 newsletter + 2,000 × 1 reactivation = 4,000 emails/month.
• Brevo Free: 300/day × 30 = 9,000 possible sends/month; storage up to 100,000 contacts; listed price $0.
• Brevo Starter alternative: $9/month × 12 = $108/year for 5,000 emails/month.
• Mailchimp: the 40,000-contact amount is pricing on request; do not estimate it from a smaller contact stop.

Worked scenario: a small list mailed frequently

Now take a product-led SaaS with 500 contacts. Every contact receives two onboarding emails, two feature messages and four weekly newsletters in a month. The send arithmetic is 500 × (2 + 2 + 4) = 500 × 8 = 4,000 emails per month. This is a small audience but a high cadence relative to its size.

Mailchimp lists Standard at $20/month at the 0–500 contact stop, with up to 12× contacts in monthly sends. At 500 contacts, that is 12 × 500 = 6,000 sends/month. The 4,000-send programme fits inside the stated allowance, and the annual arithmetic is $20 × 12 = $240. Standard also gives the team the more capable event-triggered Customer Journey path described in Mailchimp documentation.

Brevo lists Starter at $9/month starting at 5,000 emails/month, and Standard at $18/month starting at 5,000 emails/month. The 4,000-send requirement is below the selected 5,000-email point, but the Starter plan pairs that first point with storage for up to 500 contacts and includes Brevo branding. Starter’s annual arithmetic is $9 × 12 = $108; Standard’s is $18 × 12 = $216 before add-ons. If the team needs automation, A/B testing and advanced reports, the Standard feature set is the relevant Brevo comparison, while Mailchimp Standard is $240 per year at the 500-contact stop.

Brevo is cheaper on the simple send calculation, but Mailchimp can be the better operational choice if its editor, Intuit connections and journey controls save enough implementation time. The team should test one onboarding event, one reactivation branch and one newsletter approval cycle. A $24 annual difference between Brevo Standard ($216) and Mailchimp Standard ($240) is small compared with the cost of rebuilding a working lifecycle programme.

• Audience: 500 contacts.
• Send arithmetic: 500 × 8 messages per month = 4,000 monthly emails.
• Mailchimp Standard: 12 × 500 = 6,000 monthly sends; $20 × 12 = $240/year.
• Brevo Starter: 5,000 monthly-email point at $9; $9 × 12 = $108/year, with Starter branding and the 500-contact storage point.
• Brevo Standard: 5,000 monthly-email point at $18; $18 × 12 = $216/year, with automation, A/B testing and advanced reports listed.

Automation depth for onboarding, trials and product events

Mailchimp’s useful boundary is the Customer Journey tier. Its documentation says paid marketing plans have Event API access, but Essentials can use the event trigger only with a single-step flow. Standard or higher can create multi-step flows with an Event API trigger, add up to 200 steps, and use up to three triggers. An if/else split can send contacts down one of two paths based on up to five conditions. For a SaaS, that is enough to model signup, invitation accepted, first value and trial ending when those events are reliably attached to an existing audience contact.

The limitation is conceptual as well as technical. Mailchimp’s journey starts with a contact audience, so engineering must decide when a product identity becomes a marketable contact, how account context is flattened into fields, and what happens when a person belongs to two workspaces. A journey can branch on plan or activity, but it does not remove the need for an application-owned event contract. Keep required product notices separate from promotional preferences and define a stop event for activation, upgrade, cancellation and unsubscribe.

Brevo’s automation model is attractive when send volume is the main constraint and the team wants marketing and transactional paths in one vendor family. Brevo lists marketing automation, A/B testing and advanced reports on Standard. Free has a 2,000-contact automation limit. That makes the 40,000-contact quiet-list scenario feasible for occasional campaigns but unsuitable for putting every stored contact into a long-running automation. Start with a small eligible cohort, then measure the contact count actually enrolled rather than assuming storage equals automation capacity.

Neither product supplies a billing-aware SaaS lifecycle by itself. A trial ending, failed invoice or plan upgrade must arrive from the product or billing system, be authenticated, and be idempotent. For Mailchimp, send the event to an existing contact before invoking the Event API trigger. For Brevo, validate the contact attribute and automation entry path. In both cases, a simple event catalog, suppression rule and replay test will matter more than a decorative workflow canvas.

1. Name the canonical user ID, account ID, event time and plan fields before connecting the product.
2. Create one onboarding flow with an activation exit and one trial-ending branch.
3. Test duplicate, delayed, deleted and unsubscribed contacts in a staging audience.
4. Keep password resets, invoices and other required messages on a separately monitored transactional path.
5. Review contact enrollment and monthly send usage after the first complete lifecycle cycle.

Integrations: the Intuit ecosystem versus an email-volume service

Mailchimp’s ecosystem is the more visible differentiator in this comparison. Mailchimp lists Shopify, WooCommerce, Canva, Zapier, Square, Wix, Salesforce and WordPress. For a B2B SaaS, the value depends on whether one of those connectors removes custom work: Salesforce field mapping, WordPress form capture, a Zapier event hand-off or a commerce signal that starts a campaign. Mailchimp is part of Intuit, which can be relevant to a company already using Intuit products and governance processes. Treat the ecosystem as an implementation asset only after checking connector ownership, update direction, deletion behavior and rate limits.

Brevo’s pricing and feature pages reviewed here name no specific integrations. That is not proof that a connector does not exist; it means this page should not promise one. Plan a short technical spike against the Brevo API or approved connector for the CRM, product database and billing source that matter. Verify contact creation, attribute updates, suppression, retries, webhooks and export. If the team needs only scheduled campaigns and a transactional API, a smaller integration surface can be a benefit. If the team needs deep account synchronization, the discovery work may outweigh the lower monthly price.

For both tools, preserve the source-of-truth boundary. Let the product own account status and usage, let the consent system own communication permissions, and let the email platform own delivery state and campaign content. Do not treat a nightly CSV as a complete lifecycle integration: it cannot reliably express a cancellation that happened ten minutes ago, a deleted user or a payment retry. Include an audit trail for every automated change to a contact and test an unsubscribe end to end.

• Mailchimp connector checklist: field mapping, audience identity, Event API prerequisites, consent, deletion and retry behavior.
• Brevo connector checklist: API authentication, attributes, automation entry, transactional separation, webhooks and export.
• Shared rule: billing and product events stay authoritative outside the email tool; the email tool receives only the fields needed to communicate.

Migration and rollout checklist

Moving from Mailchimp to Brevo starts with a contact decision, not a CSV export. Separate active subscribers, unsubscribed contacts, bounced addresses, archived history and contacts that should be deleted. Record each person’s consent source, language, product role and last meaningful event. Map Mailchimp merge tags to Brevo attributes, then rebuild one campaign and one automation with a test cohort. Historical open and click data is not a substitute for the product events your new flows need.

Moving from Brevo to Mailchimp requires the opposite cost review. Count every stored contact that will enter a Mailchimp audience, including records retained only for suppression. Then compare that audience with the contact stop and send multiple of the target Mailchimp tier. Recreate templates and automation entry rules, but do not copy a Brevo volume assumption into Mailchimp; a 30,000-email Brevo plan and a 30,000-contact Mailchimp audience are different quantities.

Use a two-week parallel check for a B2B SaaS. Send a welcome message to a new test account, a feature announcement to an active account, a trial-ending reminder, an unsubscribed contact and a deleted contact. Compare event timing, personalization, suppression, bounce handling and reporting. Keep the old system read-only until every critical path has completed and the product metrics reconcile. The cheapest migration is the one that does not silently send a duplicate trial sequence.

1. Export and classify contacts by consent, delivery state, role, account and lifecycle stage.
2. Write a field and event mapping with an owner for each source field.
3. Rebuild one newsletter, one onboarding path and one transactional example in the destination.
4. Run representative test cases, including unsubscribe, deletion, duplicate event and failed delivery.
5. Cut over by cohort, monitor sends and suppressions, then retire the old automation after reconciliation.

How to choose for a B2B SaaS

Choose Mailchimp when the list is small enough that contact billing is comfortable, the team sends often enough to use the included multiple, and polished campaign production matters. Mailchimp Standard at $20/month for the 0–500 contact stop gives the 500-contact scenario up to 6,000 monthly sends. The Intuit ecosystem and named connectors can also reduce integration effort when your stack matches the supported paths. Plan for audience hygiene because unsubscribed and inactive records remain part of the contact conversation.

Choose Brevo when the list is large relative to its monthly send volume, when a 300-send-per-day Free allowance covers the quiet period, or when the team wants to select 5,000, 10,000, 15,000 or larger monthly volumes. Brevo Starter at $9/month for 5,000 emails can be a clean budget anchor, and its contact storage can be generous at higher volume points. Check the lower-volume contact limit, the Free automation limit, the Starter logo and every connector before committing.

If the arithmetic is close, decide on operational fit. A $24 annual gap between the worked 500-contact Standard examples is unlikely to settle a choice. Event ownership, integration maintenance, campaign review, suppression and the ability to explain the data model will. If the arithmetic is far apart, keep the scenario visible in the business case and state which contacts and sends produced it. Recalculate when the active audience, campaign cadence or product event model changes.

• Pick Mailchimp for frequent campaigns to a small audience, Customer Journeys and the Intuit-connected integration set.
• Pick Brevo for a large stored audience with light sending, or when monthly send volume is easier to budget than contact count.
• Use pricing on request for any audience or volume point the vendor does not publish; never estimate between anchors.
• Make consent, suppression, event ownership and integration tests part of the selection decision.