Pro 3 Months free unlimited transactional e-mails + 25k emails per month free forever
Free plan that allows for you to send up to 25,000 emails each month, with no credit card required. DKIM is not required (Domain Verification: (a.) Meta Tag Validation, (b.) File Creation - System can verify the domain based on the presence of a file in the root directory of the domain.). You pay only for emails that are not opened by your customers.
Pro Pay only for emails that are not opened
While other services make you pay for each email sent, Pepipost's philosophy is that email conversations should be free regardless, this way the pricing model is built around paying for emails that are not open. So it's up to you to make quality emails and make as much users as possible to open them in order to pay less.