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Email marketing tools compared (2026)
The short version: there is no single best email tool, only the right one for a job. For a creator monetising a list, Kit (free to 10,000 subscribers) and beehiiv lead. On zero budget, EmailOctopus (free to 2,500) and MailerLite go furthest. For developers, Resend and Loops are built around the API. For an online store, Klaviyo and Omnisend own the category. And if your emails will carry affiliate links, the platform's own terms matter as much as the price: GetResponse and AWeber are the most permissive; Klaviyo and ActiveCampaign are the strictest.
How we tested this
We operate one of these tools, Kit, and can speak to it first-hand. We have not run the other fifteen, so we did the next most honest thing: we fetched each vendor's own pricing and acceptable-use pages on 2026-07-03 and recorded the exact clause and its URL. The affiliate-in-email clauses are quoted with their sources in Sources below, and every row is labelled by how we know it.
We run this means a first-party fact from our own account. Researched means it comes from the vendor's official pages (or, where a vendor hides prices behind a JavaScript calculator we can't drive, a named third-party tracker), with the retrieval date. The affiliate-in-email column reads each platform's own published acceptable-use terms; the exact clause and source for every tool, Kit included, are in Sources. Prices are the headline monthly rate; annual billing is usually 10 to 20 percent cheaper, and several tools price by emails sent or active contacts rather than subscriber count, so treat the figures as the starting shape, not a quote. The full method is at the bottom, and this is a living page: we re-verify when terms change.
The matrix
Sixteen tools people actually reach for, on the five questions that decide the pick: what the free tier really gives you, what it costs at 1,000 and 10,000 subscribers, whether the platform's own terms let you put affiliate links in the mail, and who it fits.
One number is worth seeing before the full grid: how far each free tier gets you, for the tools whose free plan is measured in subscribers. Kit's is the outlier — which is a big part of why we run it.
| Tool | Free tier | ~1k subs | ~10k subs | Affiliate links in email? (their terms) | Best for |
|---|---|---|---|---|---|
| Kit | Yes — 10,000 subs | ~$39 | ~$139 | Yes, if marked; not 100% affiliate | Creators monetising a list |
| beehiiv | Yes — 2,500 subs | ~$49 | ~$99 | Yes, secondary to editorial | Newsletter creators, monetisation |
| Substack | Yes — unlimited | $0 + 10% of paid | $0 + 10% of paid | Not if promotion is the purpose | Writers, paid newsletters |
| MailerLite | Yes — 250 subs | ~$12 | ~$50 | Links yes; affiliate-as-purpose no | Zero-budget, content-first SMB |
| Ghost | Self-host only (open source) | ~$18 | ~$199 | Not addressed; opt-in required | Publishers, developers, own-your-platform |
| Mailchimp | Yes — 250 contacts | ~$13–26 | ~$100+ | Links usually OK; affiliate-marketing banned | SMB and brands sending own offers |
| Brevo | Yes — 9,000/mo | ~$9 | ~$29–65 | Not restricted in fetched terms | Cost-sensitive, large infrequent lists |
| GetResponse | Limited free + trial | ~$19 | ~$79 | Yes — only scams banned | Creators and SMB wanting funnels |
| ActiveCampaign | No — trial only | ~$15–19 | ~$149 | Extra scrutiny; affiliate-only barred | SMB wanting deep automation + CRM |
| Constant Contact | No — trial only | ~$30 | ~$155 | Not addressed; crypto banned | Local business, support-first |
| Klaviyo | Yes — 250 profiles | ~$30 | ~$150 | No — bars affiliate-primary sends | Ecommerce brands, deep data |
| Omnisend | Yes — 250 contacts | ~$16 | ~$132 | No commission-only affiliate | Ecommerce, email + SMS |
| Resend | Yes — 3,000 emails/mo | ~$20 | Metered by sends | Not addressed; opt-in only | Developers, API-first sending |
| Loops | Yes — 1,000 contacts | ~$49 | ~$99 | Recipients must be your product's users | SaaS founders, product email |
| AWeber | Yes — 500 subs | ~$20 | ~$80 | Yes — not prohibited | Affiliate-leaning creators, zero-budget |
| EmailOctopus | Yes — 2,500 subs | ~$9–14 | ~$44 | Allowed, extra scrutiny | Zero-budget, simple sending |
The affiliate-link question most roundups skip
If you plan to earn from affiliate links in your emails, the platform you send through can shut you down for it, separately from whatever the affiliate program allows. We read each tool's own acceptable-use terms. Three groups emerged; every clause below is quoted with its source in Sources.
Permissive. GetResponse bans only "make-money-fast schemes, chain letters, pyramid schemes" and never names affiliate marketing. AWeber's service agreement does not prohibit affiliate promotion at all. Brevo restricts purchased lists but not affiliate content in the terms we could read.
Conditional — links yes, affiliate-as-your-whole-model no. Kit allows affiliate links "as long as they are properly marked and used responsibly" but bars content that is "100% affiliate based". Mailchimp draws the same line: "affiliate marketing as an industry is prohibited", yet "affiliate links are usually fine". MailerLite, beehiiv and Substack all permit occasional, disclosed links but prohibit sending built primarily to push offers. EmailOctopus allows it and flags affiliate accounts for a manual review.
Strict. Klaviyo prohibits "promotions for the primary purpose of affiliate marketing … where you have no direct relationship to the promoted product". Omnisend bars "affiliate marketing where you have no direct relationship with the merchant". ActiveCampaign puts affiliate marketing under "additional scrutiny" and disallows using it solely for affiliate offers. Loops requires that recipients "registered with your software product … or engaged in a business relationship with you", which rules out a cold affiliate list.
Whether the affiliate program (Amazon Associates and the rest) also allows email is a different question with its own answer — that comparison is our affiliate-programs-in-email page. A safe setup needs a yes on both.
Best for your job (not a universal winner)
Creator monetising a list. Kit is our pick and the tool we run: free to 10,000 subscribers, an affiliate-friendly policy, and a clean API. beehiiv rivals it on native monetisation. Not for you if you sell physical products at scale (an ecommerce tool fits better) or want the absolute cheapest bill (MailerLite and EmailOctopus undercut it).
Zero budget. EmailOctopus (2,500 free subscribers) and Brevo (9,000 free emails a month) go furthest before you pay; MailerLite and AWeber have real free tiers too. Not for you if you need advanced behavioural automation, which the cheap tiers lack.
Developer or API-first. Resend ("the email API for developers", with React Email) and Loops (event-driven, built for SaaS) are designed to be run from code. Not for you if you're a non-technical creator: both assume you send from an app, and Loops requires recipients be your product's users.
Online store. Klaviyo and Omnisend are built on the ecommerce data model, with SMS and cart flows. Not for you if your model is affiliate content: both platforms restrict affiliate-primary sending, and Klaviyo bills by your whole active-profile count, which climbs fast.
Established SMB wanting automation and a CRM. ActiveCampaign has the deepest automation here; GetResponse bundles landing pages and webinars. Not for you if you're affiliate-led (ActiveCampaign scrutinises that) or want a free tier (it has none).
What this page doesn't know yet
We have sent real email through Kit only, so deliverability, support quality, and the day-two annoyances of the other fifteen are researched rather than lived. As our own operation grows we'll add first-party numbers where we earn them and say so. Several vendors (Klaviyo, MailerLite, Omnisend, Loops, ActiveCampaign, Constant Contact) render exact tiered prices in a JavaScript calculator we can't drive from a fetch, so those figures come from the vendor's starting price plus named trackers and are approximate; check the live calculator before you commit. Acceptable-use terms change, so every policy call here carries a retrieval date and gets re-verified.
Method: replicate this check yourself
Roughly ten minutes per tool.
1. Open the vendor's own pricing page and read the free-tier limit and the plan
that covers your list size. If the price sits behind a slider, note it's calculator-gated and
cross-check one independent tracker.
2. Find the platform's acceptable-use policy or terms (search
site:vendor.com acceptable use) and read for affiliate,
affiliate marketing, purchased lists, and opt-in. Absence of the word
"affiliate" is itself an answer.
3. Record the quote, the URL, and the date. Terms change; undated quotes rot.
4. Distrust any comparison that ranks tools without showing the clause, this one
included. That's why we quote the affiliate clause and link the source for every tool in
Sources.
Questions we kept having to answer
Is a tool's policy on affiliate links the same thing as an affiliate program's rules?
No, and this is the part most comparisons blur. A tool's acceptable-use policy governs what you can put inside the emails you send through that tool, any affiliate link, to any program. An affiliate program's terms govern whether that specific program lets its links travel by email at all. Kit shows up as an example of both, because Kit is a sending tool with its own acceptable-use rule about affiliate content, and separately runs its own affiliate program that pays a commission for referrals. Those are two different Kit policies. This page answers the first question, for sixteen tools; our affiliate-programs-in-email page answers the second, for four programs.
Can an email platform really suspend my account over an affiliate link?
Yes, if the platform decides the link violates its acceptable-use terms, independent of anything the affiliate program itself allows. Several platforms in this comparison flag affiliate content for manual account review, and a few prohibit sending built primarily to push commission links. Read the platform's own terms before you build a strategy around affiliate email, since the sending tool can shut the channel down even where the program permits it.
Which of these tools is free forever, and which is just a trial?
Kit, beehiiv, Substack, MailerLite, Mailchimp, Brevo, Klaviyo, Omnisend, Resend, Loops, AWeber, and EmailOctopus each carry a standing free tier with a real subscriber or send limit, no expiry date. GetResponse's free plan is limited and paired with a full-feature trial. ActiveCampaign and Constant Contact have no free plan at all, only a time-boxed trial. Ghost has no managed free tier, though the open-source software itself is free if you run your own server.
Do the prices above include any commission we earn?
No. The prices are what the vendor charges you; our commission, where we have one, comes from Kit separately and does not change what you pay. We disclose which links are ours in the box at the top of this page.
Sources: the affiliate-in-email clause, per tool
Each platform's own acceptable-use terms, quoted, with the page and the date we read it. This is the sending platform's policy, separate from any affiliate program's rules. Where a vendor's terms are silent or blocked our fetch, we say so rather than guess.
Kit. "We do not restrict the use of affiliate links in emails as long as they are properly marked and used responsibly," and it disallows content that is "100% affiliate based."
beehiiv. "While the occasional use of affiliate links is allowed, Content created primarily for affiliate marketing or lead generation purposes are not permitted on beehiiv."
Substack. "We don't permit publications whose primary purpose is to advertise external products or services, drive traffic to third party sites, distribute offers and promotions, enhance search engine optimization, or similar activities."
MailerLite. "You may include affiliate links in your campaigns, provided they are clearly presented as offers from another company," but "Affiliate marketing, defined as the promotion of multiple referral links from various third-party companies purely to generate commission-based income, is strictly prohibited."
Ghost. No affiliate clause in the terms we fetched; permission-based sending is required: "all recipients must have opted-in to receive communications from the sending entity."
Mailchimp. "Affiliate marketing as an industry is prohibited under our Terms of Use," yet "affiliate links are usually fine to use in Mailchimp emails" when "your main message isn't centered around affiliate links."
Brevo. No affiliate clause in the terms our fetch could read (the page partly blocked automated access); purchased and scraped lists are prohibited. Verify in a browser before relying.
GetResponse. Prohibits "fraudulent goods, services, schemes, or promotions (e.g. make-money-fast schemes, chain letters, pyramid schemes)"; affiliate marketing is not named.
ActiveCampaign. Lists "affiliate marketing" under "Content and Industries Subject to Additional Scrutiny," and prohibits content that "Promotes any pyramid schemes, multilevel marketing opportunities, 'get rich quick' schemes."
Constant Contact. Lists "affiliate marketing" as scrutinized content and requires opt-in-only lists; cryptocurrency is prohibited; affiliate links are not otherwise addressed.
Klaviyo. Prohibits "Promotions for the primary purpose of affiliate marketing, including but not limited to communications where you have no direct relationship to the promoted product or service other than affiliate commissions or links."
Omnisend. Prohibits "Affiliate marketing where you have no direct relationship with the merchant or product other than earning commissions."
Resend. No affiliate clause; consent is required: "All mail must be sent to recipients who have explicitly opted in to receive communications from you."
Loops. "All recipients must have registered with your software product, have otherwise explicitly engaged with your software, signed up for your marketing email list, or engaged in a business relationship with you."
AWeber. Its service agreement does not prohibit affiliate promotion; it bars spam and purchased lists: "Importing or in any way using purchased leads with an AWeber account is strictly prohibited."
EmailOctopus. Lists "affiliate marketing" among industries "subject to additional scrutiny during an account review"; it is not banned.
Changelog
This page updates when pricing or terms change. Want the change notices?