Free email services do cap the number of email messages you can send out per day. This is to cut down on spam messages sent with their services. The cap is generally around 100 messages per day, which is sufficient for keeping in touch with family or other personal email uses. But if you need an email service for business purposes, it may be better to purchase an email service that permits unlimited messages each day.
www.constantcontact.com (Not Free - But 60 Day Free Trial): Constant Contact email services blends your email campaigns and your social networking campaigns into a single matchless and easy-to-use service. They provide an email marketing service with 400+ customizable templates and the option to insert text or your own HTML code into the emails. you also get a 60-day-free-trial with this email marketing service.
dotmailer is a marketing automation platform that empowers B2B, B2C and e-commerce businesses. The software enables marketers in 150 countries to use advanced data to design, test and send powerful automated campaigns. In addition to being a Magento Premier Technology Partner, dotmailer integrates seamlessly with other ecommerce platforms and CRMs.