Most comparisons of ConvertKit and MailerLite are written for bloggers who want to grow a newsletter, sell a course, or build a personal brand. They score the tools on editor flexibility, subscriber limits, and whether you can design a pretty welcome email. None of that tells you what you actually need to know: which platform lets you segment a list by the exact affiliate link someone clicked, and which one is less likely to flag your promotional emails as spam before a reader ever sees them.
Affiliate marketing email has different requirements than a typical newsletter. You are sending links to third-party offers, often repeatedly, often to the same segment of people who showed interest in one product category. Spam filters watch for that pattern. Some email providers watch for it too, and their terms of service say so. This comparison scores ConvertKit and MailerLite against those specific pressures, not against generic email marketing features.
Tagging and automation: segmenting by what they clicked
This is where the two platforms diverge the most for affiliate use.
ConvertKit builds its entire system around tags and visual automations rather than rigid lists. When a subscriber clicks a link in an email, you can automatically tag them, move them into a different sequence, or trigger a follow-up based on that one action. For an affiliate funnel where you are sending different offers to people based on prior interest, this matters: someone who clicked a link to a hosting review can land in a different sequence than someone who clicked a link to an email tool review, without you manually sorting anyone.
MailerLite has caught up considerably on this front. Its automation builder now supports click-based triggers and tagging too, and the interface is arguably easier for a beginner to read at a glance. Where it still lags is in how deeply you can branch a sequence based on multiple conditions at once. ConvertKit’s automations handle layered logic, such as “clicked link A and did not click link B,” more cleanly.
For a reader running one or two affiliate offers, either tool segments well enough. For someone running a funnel with several products in rotation, ConvertKit’s tagging system scales better without turning into a tangle.
Deliverability and promotional content
Deliverability is the part generic reviews skip entirely, and it is the part that decides whether your affiliate emails get read at all.
Both platforms maintain decent sender reputations, but affiliate content behaves differently in the inbox than a personal update or a blog recap. Emails with multiple outbound links to commercial offers, repeated across a list, draw more scrutiny from inbox providers like Gmail and Outlook. ConvertKit’s infrastructure has generally handled this kind of sending pattern well, partly because its user base already skews toward creators who monetize through links, affiliate or otherwise, so its sending reputation isn’t built on a population allergic to commercial content.
MailerLite’s user base leans more toward small businesses and ecommerce brands sending transactional and promotional email, which is a different kind of sending pattern than a daily affiliate roundup. That isn’t a deliverability problem by itself, but it means affiliate-heavy sending is less central to how the platform is used, and support may be less familiar with optimizing for it.
Neither platform publishes affiliate-specific deliverability guarantees, so the practical move is the same regardless of which you pick: warm up a new account slowly, avoid cramming a message with affiliate links, and keep an eye on open rates in the first few sends rather than assuming the platform will handle reputation for you.
Terms of service: what each platform actually allows
This is the section that causes the most trouble for affiliate marketers after the fact, because nobody reads the terms until an account gets flagged.
ConvertKit has generally positioned itself as creator-friendly, including toward creators who monetize through affiliate links, and its terms don’t single out affiliate marketing as a restricted use case the way some providers do. That said, it still prohibits the usual list hygiene violations: purchased lists, scraped addresses, and content that misrepresents the sender.
MailerLite has historically taken a more cautious stance on affiliate marketing specifically, and accounts that send a high volume of affiliate links, particularly in certain niches like finance or health, have faced manual review or requests for clarification. This isn’t unique to MailerLite among email providers, but it’s worth knowing going in rather than discovering it after your list has grown and a campaign gets held up for review.
Neither platform’s terms are static, and the practical lesson for both is the same: disclose affiliate relationships clearly in the email itself, which is good practice regardless of platform, and keep your content oriented around genuine recommendations rather than link dumps. If you haven’t worked through why that discipline matters beyond compliance, disclosure as a trust strategy covers the reader-trust side of it.
Templates, landing pages and signup forms
Capturing affiliate traffic into a list is the step before any of the segmentation or automation matters, and both tools handle it differently.
ConvertKit’s landing pages and forms are built with simplicity as the priority. They convert well because they’re uncluttered, and they integrate smoothly with the tagging system, so a form embedded on a review page can tag a subscriber by which post they signed up from. That’s useful if you’re building separate lists around separate content topics or product categories.
MailerLite offers a broader set of template designs and a more flexible drag-and-drop builder, which suits someone who wants more visual control over a landing page without reaching for a separate page builder. If your affiliate pages are already built in WordPress with a tool like the ones compared in Elementor vs Beaver Builder, MailerLite’s forms embed easily into either, and so do ConvertKit’s.
Neither platform is a reason to choose the other on this point alone. Pick based on whether you want a simple form that tags cleanly or a flexible builder with more design options.
Pricing as your list grows past the free tier
Both platforms offer a free plan aimed at getting a small list started, and both move to subscriber-based pricing once you grow past it. The exact thresholds and rates change often enough that quoting numbers here would be out of date by the time this is read, so the more useful comparison is structural.
ConvertKit’s pricing is based on total subscribers regardless of how many tags or automations you run, which means a list segmented heavily by affiliate link clicks doesn’t cost more just because it’s organized into many tags. MailerLite’s pricing works similarly, based on subscriber count rather than feature access, though some of its more advanced automation features are gated to higher tiers.
The practical difference shows up as your list grows and you start running more affiliate campaigns in parallel. ConvertKit’s higher tiers lean toward creators who need deeper automation logic, which affiliate marketers running multiple offers tend to need. MailerLite’s higher tiers stay competitively priced but the automation ceiling is lower, which matters less if you’re promoting one or two offers and more once you’re running several.
Check current pricing directly on each provider’s site before committing, since both have changed their tier structures more than once.
Which one fits a funnel like the one in Building an Affiliate Email Funnel
If you’re setting up a funnel along the lines described in Building an Affiliate Email Funnel That Actually Converts, where subscribers move through a sequence based on which offer they engaged with, ConvertKit’s tag-based automation maps onto that structure more directly. You can tag a subscriber at the point of signup, tag them again based on link clicks inside the sequence, and branch the funnel without rebuilding it from scratch each time you add a new offer.
MailerLite can run the same funnel, and for a single-offer sequence the difference is small. The gap opens once the funnel branches into multiple paths based on multiple possible actions, which is where ConvertKit’s automation logic has more headroom.
The verdict for three affiliate marketer profiles
Just starting out, one offer, building your first list. Either platform works. MailerLite’s free tier and simpler interface make it an easy place to start if you haven’t built automations before. ConvertKit is just as approachable and saves you a future migration if you expect to grow into more complex segmentation.
Running a handful of offers, segmenting by interest. ConvertKit’s tagging and automation logic handles branching sequences more cleanly, and its creator-friendly terms give more room for affiliate-heavy sending without second-guessing.
Scaling into a larger list with multiple funnels running at once. ConvertKit again, mainly for the automation depth and the deliverability track record among a sender base that already sends commercial content. If budget is the deciding factor at this stage, MailerLite’s pricing stays competitive, but weigh that against the automation ceiling before you commit a growing list to it.
Once you’ve picked a provider, put it to work with the structure in Building an Affiliate Email Funnel That Actually Converts.
