Short verdict
Choose ConvertKit when the business is audience-led and newsletter strategy is central. Choose MailerLite when the business wants a simpler, lower-overhead newsletter platform for conventional small-business use.
Pricing considerations
MailerLite is usually easier to justify for mainstream small-business newsletters. ConvertKit becomes better value when the audience itself is strategically important and the business uses the more subscriber-led workflow model properly.
Ease of use comparison
Both are approachable, but ConvertKit assumes a more audience-led way of thinking about subscribers. MailerLite is the simpler fit for businesses that just want a low-friction campaign and list workflow.
Implementation and migration comparison
Both are relatively easy to implement. ConvertKit migration is easiest when the existing setup is already newsletter- or audience-led, while MailerLite is often easier for more conventional campaign structures.
UK small business suitability
ConvertKit suits UK audience-led businesses, creators and education-led brands. MailerLite suits a broader range of UK SMBs that want simple newsletters and light nurture without a more specialised model.
Automation capabilities
ConvertKit is stronger for subscriber nurture and audience-led automation. MailerLite is strong enough for lighter nurture, but it is not built around the same audience-first logic.
Segmentation capabilities
ConvertKit is better when the business organises subscribers by interest, offer or audience intent. MailerLite is better when simpler list grouping and straightforward campaign targeting are enough.
Deliverability considerations
Both can support healthy deliverability if lists are permission-based and engagement is maintained. ConvertKit’s model works best when the audience is genuinely opted in and newsletter-led.
Watch-outs
The main watch-out is choosing ConvertKit because it sounds more specialised when the business actually needs a simpler, broader newsletter workflow.