Home › Guides › Email marketing hidden fees
Updated September 25, 2026 · Prices verified from vendor pricing pages, September 2026 · Affiliate disclosure
An email platform's invoice is a function of at least four inputs: list size, send volume, seats, and time. The pricing page usually prices the first one and stays quiet about the rest. Two vendors can quote the same headline number for the same list and still land a year apart, because one bills the contacts who stayed and the other bills everyone who ever signed up; because one sells sending capacity and the other sells names; because one discounted your first year and quietly un-discounts the second.
This page is a field guide to the seven charges that do that work. Each one is documented from the vendor's own pricing page or plan FAQ, with the month we read it; where a vendor publishes no figure, the table says so. The goal is not to rank vendors by innocence — it is to make the twenty minutes you spend at checkout cover the charges that arrive in month two and month thirteen.
| Charge | Mailchimp | MailerLite | Brevo | Kit | ActiveCampaign | GetResponse | Klaviyo |
|---|---|---|---|---|---|---|---|
| 1 · Self-billing overage | Yes — invoices automatically | Band step instead (at anniversary) | — | — | — | — | — |
| 2 · Left contacts still bill | Yes — unsubscribed count | No — active only | No contact-based billing at all | — | — | — | Active profiles only |
| 3 · Credits expire monthly | Yes — SMS credit blocks | — | Plan sends reset monthly; PAYG credits do not expire | — | — | — | — |
| 4 · Discount with an expiry date | $10/mo × 12 months, then $20 | None published | — | — | — | Promo meta "from $13.30/mo" | $19 off first month, 500-profile plan only |
| 5 · Annual discount you can't reach | Only ≥10,000 contacts, via sales | 10% on every band, printed | Annual billing on published plans | Annual: $390 Creator | Monthly ≈ +20%, shown at checkout | 18% off 12-month prepay | None published |
| 6 · Percentage of revenue | — | — | — | 3.5% + $0.30 per digital sale | — | — | — |
| 7 · Add-ons at checkout | Seat/audience caps push the plan up | — | No-logo add-on $10.80/mo | — | — | — | — |
Read from each vendor's own pricing page, plan documentation or checkout flow, September 2026. A dash means we found no published charge of that type for that vendor's email plans — it is not a promise that none exists. Klaviyo's rows reflect its email plan ladder read on September 24, 2026.
Mailchimp's plan documentation states the mechanic plainly: exceed the contact band or the monthly send allowance on a paid plan, and the overage is billed automatically — campaigns keep running as long as the overage is paid on time. Nothing pauses for approval. The first notification is the invoice, which makes the overage the purest hidden fee in the category: it is triggered by success, priced by the vendor, and discovered by the buyer at statement time.
MailerLite's mechanic differs in shape but not in surprise. It moves the whole account to the next band's price at the billing anniversary, and the count is cumulative inside the cycle — any address active at any point counts, even if deleted afterwards. Cross from 2,500 to 2,501 subscribers and the next bill is the 5,000 band: $49 instead of $33, a 48% step for one name. The step is at least a published number on a published ladder, which is more than an auto-invoiced overage can say — but it lands just as unannounced.
This is the fee most buyers never notice because it never appears as a line item. Mailchimp bills the contacts in your audience — subscribed, unsubscribed, non-subscribed — so the address that opted out in March keeps costing money until it is archived or deleted by hand. MailerLite bills active subscribers only, so unsubscribes and bounces drop off the count by themselves. Klaviyo prices on active profiles, which puts it closer to MailerLite than to Mailchimp on this axis.
The size of the gap depends entirely on the age and hygiene of the list, which is why no vendor publishes it. On a freshly built list it is near zero. On a list five years deep with a third of the names cold, it is the difference between billing 10,000 contacts and billing 7,000 — the same content, the same sends, two different bills.
Mailchimp sells SMS as credit blocks outside the email plan: they auto-renew, and unused credits expire at the end of each month. That combination — automatic repurchase plus monthly expiry — is how a budgeted $20-a-month add-on becomes an unbudgeted standing charge. Brevo's structure is gentler but the same idea: on its subscription plans the send allowance resets each month, while its pay-as-you-go credits are the exception that does not expire. The practical rule: anything billed in credits should be checked for two words — renew and expire — before it goes on the card.
Mailchimp's US page runs Standard at $10 a month for twelve months on the 0–500 band, against a $20 list price. The first year costs $120; the second costs $240 for the identical service. The step at month thirteen is 100%, and it is the single largest price change most Mailchimp buyers ever experience — larger than any band jump at small list sizes, and larger than any overage.
The pattern is category-wide. Klaviyo's banner offers $19 off the first month of its 500-profile plan — a first month at $1 against a $20 list price — on that plan only. GetResponse's advertising meta promotes "from $13.30/mo", a promotional reading of its $19 Starter price with the prepayment discount applied. None of this is concealed; all of it is priced to be found by the buyer who compares month one and forgotten by month four. The honest comparison number is always the month-four figure.
Annual billing is the largest published saving in the category, and the fine print decides who gets it. MailerLite prints 10% on every band of both plans, unconditionally: $12 becomes $10.80, $89 becomes $80.10. GetResponse advertises 18% off twelve-month prepayment. Kit publishes annual figures outright ($390 a year for Creator against $33 a month).
The other side of the ledger: Mailchimp's own footnotes restrict annual plans to Premium and to Standard plans of 10,000-plus contacts, arranged through its sales team — a buyer with 2,500 contacts has no annual option to buy. Klaviyo publishes monthly prices only, with no annual discount on the page as of September 2026, so the annual figure is arithmetic (monthly × 12), not an offer. ActiveCampaign publishes annual anchors ($15 a month for Starter at 1,000 contacts, billed yearly) while its monthly rates run roughly 20% higher — and per our reading, that monthly figure appears at checkout rather than on the pricing page. When a vendor's cheapest quoted cycle is the one you cannot use, the quote is not your price.
Kit's email plans carry a transaction fee on digital product sales: 3.5% of the transaction plus $0.30, on all three tiers. On $1,000 of digital sales across 100 orders in a month, that is $65 (3.5% × $1,000, plus $0.30 × 100 — our arithmetic, not a vendor quote). The fee is printed clearly on Kit's pricing table, so it fails the "hidden" test narrowly — but it is the only charge on this page that scales with revenue rather than with list size, and it is invisible on every bill that does not include a sale. A creator comparing Kit's $0-to-10,000-subscriber free plan against a conventional vendor's $12 should price their own monthly sales into the comparison before concluding which one is cheaper.
Brevo charges $10.80 a month to remove its logo from emails — $129.60 a year, which is more than its own Starter plan costs billed annually ($96.96). The comparison is not an argument against Brevo's pricing; it is a demonstration of how an add-on can outgrow the plan it attaches to. Mailchimp's version of the same mechanism is caps instead of add-ons: users and audiences are limited to 1, 3, 5 or unlimited by plan, so a fourth team member is not a fee but a forced upgrade to the next plan tier — priced in the plan ladder rather than on a line item, and just as unbudgeted.
It is worth restating why these seven charges resist comparison shopping. A buyer comparing two vendors side by side compares the numbers on the pages; the seven charges live in plan terms, FAQs and checkout flows, which nobody tabs open. Our MailerLite vs Mailchimp head-to-head shows what happens when both vendors actually do bill on the same axis — the comparison becomes clean, and what remains visible is exactly this transparency gap: one ladder printed in full, the other rendered one selection at a time.
One vendor, read line by line, shows how the charges stack on a single bill: our Mailchimp pricing and hidden costs guide works through its three caps — contacts, sends, seats — and the six charges that land after checkout, from auto-billed overages to the month-thirteen step. If the audit turns up enough to justify moving, our Mailchimp alternatives guide prices five vendors from their own pages, and the list-size cost calculator prices your own subscriber count on both billing cycles before any fee has a chance to surprise you.
Every figure comes from the vendor's own pricing page, plan documentation or checkout flow, read in September 2026 and dated on this page; Klaviyo's email-plan ladder was read on September 24, 2026. Where a mechanism is described in a vendor FAQ rather than priced on a page, we say so. Where a vendor publishes no charge of a given type, the table shows a dash rather than an inference, because absence of evidence on a pricing page is not a promise about an invoice. The per-fee rows above compress longer treatments: Mailchimp's caps and after-checkout charges are read line by line in our Mailchimp guide, the two contact-band ladders are compared band by band in our MailerLite vs Mailchimp head-to-head, Brevo's and MailerLite's billing models are priced at three list sizes in our Brevo vs MailerLite comparison, and our methodology page explains how figures are verified and dated.
Seven, as documented from official pages in September 2026: self-billing overages, contacts that still count after unsubscribing, credits that expire monthly, introductory discounts that revert (Mailchimp's $10 promotional month becomes $20 in month thirteen), annual discounts gated by list size or sales teams, transaction fees on product sales (Kit's 3.5% plus $0.30), and per-seat or branding add-ons. Every platform we read carries at least one; most carry three.
Yes. Mailchimp bills the contacts sitting in your audience, including unsubscribed and non-subscribed ones, until they are archived or deleted. MailerLite bills active subscribers only, and unsubscribes drop off its count automatically. On an aged list, this is often the single largest unpriced difference between the two bills.
The three usual causes: a promotional rate expired (Mailchimp's twelve-month $10 offer reverts to $20 — a 100% step), the list crossed a contact band (MailerLite steps from $33 at 2,500 subscribers to $49 at 5,000 — a 48% step for one name), or an overage was invoiced automatically after the contact or send allowance was exceeded.
Klaviyo publishes monthly prices only as of September 2026, so its annual figure is twelve times the monthly price rather than an offer. Mailchimp restricts annual plans to Premium and Standard plans of 10,000-plus contacts through sales. ActiveCampaign publishes annual anchors while its monthly rates run roughly 20% higher, visible at checkout. MailerLite prints 10% yearly on every band; GetResponse advertises 18% off twelve-month prepayment.
Five checks take about twenty minutes: photograph the final checkout price before paying, since some vendors show the true monthly figure only there; search the vendor's FAQ for overage and refund wording; ask what happens at one subscriber past the published band; count your seats and audiences against the plan caps; and write the promotional price's expiry month on the calendar the day you sign up.