Squarespace Email Campaigns - Email, but pretty.
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Lob - A simple API to integrate print & mail solutions into your applications.
Brevo - Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.
PostGrid - Transform your Offline Communications. Use our fully-documented REST API to send personalized letters, checks, postcards and improve address accuracy.
Campaign Monitor - Email marketing software built for designers and their clients to run successful email campaigns.