SendInBlue 9,000 emails per month (daily limit of 300) for an unlimited number of subscribers. You can have a maximum of 2,000 subscribers in your automated campaigns at any time. A good range of advanced autoresponders is offered on the free plan, including welcome, anniversary, page visits and ecommerce (such as product purchase or abandoned cart). You also get an allowance for free transactional emails. SMS can also be added for an extra cost. (Full review)
An auto responder campaign is one of six campaign types and is used to send a one-time email to contacts after they subscribe to your list. You can use this campaign type to send a "Welcome" message to contacts as soon as they subscribe to your list, or use it to send a "Check in" message a certain number of days/hours after contacts subscribe to your list.  
Where they should improve: Unfortunately, this ease of use doesn’t apply to the autoresponder editor. You can’t view autoresponders in a workflow, and they’re not very flexible (you can’t send autoresponders to send after an hour, for example, and you can’t set sending time ranges). Historically, Benchmark haven’t performed so great in our deliverability tests, either.

Like any marketing strategy, building an email marketing campaign strategy relies on knowing your audience. That means checking out analytics and social media analytics for demographic information. Once you know who your subscribers are, it’s easy to come up with a lead magnet such as an ebook that will encourage them to subscribe. That also makes it easier to decide on the right content for your email. If you can, give subscribers options about how often they hear from you.
Netsuite is an advanced marketing automation software capable of automating various marketing specific processes, flows, and tasks. You can use the platform to create multiple campaigns and align the same with your sales team. The execution of multiple marketing campaigns driven by email, social media, event management, and others can be streamlined effortlessly using Netsuite.
When a subscriber is sorted into a segment, it can trigger an automation to send to them. Each person’s interactions with your email campaigns or your website can trigger a sequence of follow-up emails based on their interests, allowing you to hone your message to your targeted audience. For example, if someone visits your pricing page, you know they’re probably further down your sales funnel and will want to follow-up appropriately. Or if they went to a specific product page or clicked on a link for that product, you can send additional information about the product, testimonials and more.
Build your audience and manage your contact groups. Install our opt-in widget on your website to capture email addresses and automatically sync to contact lists in your account. Upload your own contact lists as either a CSV, TXT or XLS files. Our system will seamlessly integrate into your CRM acting as your second pair of eyes, filtering out unsubscribes and possible errors.
As a growing business, you may also be looking for a CRM solution, and you'll find that the more advanced email marketing services have begun to crossover into CRM. It makes sense: Both types of software deal with managing and communicating with customers. A handful of these services are one-stop shops, either offering both email marketing and CRM out of the box or as add-on services.
I do find that Ontraport seems to have great pricing overall (and yes, a lot less functions you need to get a plugin or workaround for – I wonder when you have a platform you pay a lot for and then there is a big side industry of people doing training and also developing plug ins – I think if you pay for a product that product should really keep developing and adding those plugins ‘in product’ and I can see that Landon and his team are continuing to refine and add functionality that is requested, so I can’t fault their customer service).
iContact Pro is a marketing campaign management suite built for small startups to medium-sized companies. It offers simple yet email marketing, segmentation, social posting, and workflow automation features that let you cut through the digital noise. Mobile-ready, it is also equipped with reporting and lead scoring tools for data analysis. To purchase iContact Pro, you may opt for their monthly billing plan or annual prepay that are priced according to the number of subscribers. You may also choose their Premier plan which is available by-quote.

Unsubscribe rate. Unsubscribes are always going to happen no matter what, and that’s usually OK because those people probably would never have bought from you anyway. However, a high unsubscribe rate can indicate that you are losing potential customers. Check the following: Why did people subscribe to your list in the first place, and are you delivering on that promise? Is the content of your autoresponder highly relevant to the segment it is being sent to? Are you sending too many sales emails with too little value emails? (Recommended reading: 5 Reasons Why People Unsubscribe from Your Email List.)
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