Marketing Email Service Provider (ESP) Comparison and Review

Comparison to find the best marketing email service provider.

The top marketing email service provider needs to have a balance of its  services to make it the best. The three marketing email service providers ESP’s are: Constant Contact, Aweber and Vertical Response

Marketing email service providers (ESP) are a great way to get you your company up-and-going with an email solution in a short amount of time without building an email infrastructure. You will be sending your email newsletters, marketing emails and other correspondence as fast as you can get your clients to subscribe.

All ESP’s now require that all your email leads sign up through their system, so moving a large list from one ESP to another is virtually impossible, as one ESP will not trust the methods of another ESP. Some ESP’s will require access to your old ESP system before they will allow the transfer of leads (Yes, that’s you AWeber) that’s a very odd and dangerous precedent, allowing your new potential ESP to access your old account on a competing ESP.

Marketing email service provider ESP’s are not without their challenges, we examine various web based email ESP systems below including Constant Contact, A Weber Communications and Vertical Response and their appropriate pros and cons.

Reviews of this kind are often done by journalists or writers who have few IT skills and don’t actually send out big emails to a list of their clients and thus have very little “skin in the game” or knowledge of sending hundreds of thousands of emails per month – they focus on things that really don’t matter and miss things that are critical. That’s where our team excels, so you should find their results interesting.


AWeber Summary:

Founded in 1998, AWeber Communications helps small businesses automate email follow up and newsletter delivery and has been a stalwart marketing email service provider since its inception.
This small (21 person) Newtown, Pennsylvania based operation focuses on great customer support providing their permission-based email marketing service.


  1. All you can eat price model. Pay once a month and send as many emails as you like
    (Send too many though and your clients will start ignoring them)
  2. Simple, easy to use GUI
  3. Good telephone support, fast to answer, knowledgeable people, and no outsourced “India Phone Hell”


  1. Your account is forced to use a unique list name that contains an identifier. When your clients join your list, it welcomes them to an Aweber list name – This looks unprofessional to your clients, especially if you don’t want them to know that you are using an email service provider (ESP) instead of running your own. This is especially bad if you decide to ever move to another service, this could, after all, be AWeber’s master plan to stop you from moving.
  2. Email arrives at your clients desktop with an “on behalf of” message E.G.; on behalf of;
  3. Clearly this should be, but they won’t allow that setting. Other ESP’s have figured out how to get around this (using fake header actually) AWeber has not.
  4. The unsubscribe link font cannot be changed to match your email design, you are stuck with large unsightly black Times New Roman 14 link , again quite unprofessional looking, poorly aligned with your own email design – the text stands out like a sore thumb, a bloody, dripping sore thumb.
  5. The unsubscribe link contains an address, where does this company stop promoting themselves? – After all, you do pay heavily for this service and your email is supposed to be coming from you, why should you be promoting them in YOUR email? At the very least it should be a non-descript URL like other ESP’s use.

AWeber is a decent attempt at an ESP, they have invested well in support staff, but clearly lack a good technical ESP solution to play with the big boys. Your email will appear amateurish, but if you an amateur that might be a perfect fit.

Constant Contact

Constant Contact Summary:

With over 320 employees based in two locations (Waltham, Mass and Loveland, Colorado) this behemoth in the marketing email service provider ESP industry has become the Ford Factory of ESP’s providing email marketing solutions to small businesses. The general focus of this company is the much “Smaller” business with only 3% of their clients having over 100,000 contacts in their databases.


All you can eat pricing model. Pay once a month and send as many emails as you like (Too many and your client list will switch off)

Good feature set including some overlooked “gems” like the ability to “Send to all new contacts since email was last sent”, masterstroke!


Complicated GUI, tries to pitch you a multitude of other useless Constant Contact products, when all you want is to send email to your client list

The single tech support team at Constant Contact tries to provide support for everything from “Mom and Pop shops” to ” large corporations” which is a poor fit for both. They treat everyone the same, which doesn’t work for either end of the spectrum

In an email you cannot insert field data (Like first name or last name) in text based emails, this feature is only works in HTML emails.
What’s worse is that that it appears that the feature is available, but in actual use it fails in such a way that it damages your brand – they insert the wrong words into your text based emails making you look like a chump to your clients. Fred Smith will receive a text based email that says “Hi Frank Scmidt” – at the time of writing Constant Contact confirms that this is still a problem.

Constant Contact forces their clients to include a “Constant Contact” logo at the bottom of every email. If you complain they will remove, but it’s the default for all customers.

Support staff at this marketing email service provider can be arrogant, faceless, nameless human beings, who have little accountability for their own errors. When problems do arise customers are forced to work through a “level 2″ person, who often doesn’t understand the problem – they are the only ones “allowed” to talk with the other departments (Like compliance) to get things resolved. Compliance department operate in an ivory tower and never speak to clients.

The infamous problem of data loss continues to dog Constant Contact. The way it works is If your account is put on list review, and you don’t realize it, any contacts that are added during this time cannot be sent an email later (When everything is cleared up) through the “Resend to contact added” button. Constant Contact confirms that they have had this error on their list of “To Do’s” for 7 years, poor show.

Facebook and Twitter integration tools as well as the image hosting tools are poorly designed and fail to provide clients with what they actually need.

Some development and support is outsourced to India, resulting in lower costs for the company, but lower quality for the client.

Constant Contact has a powerful technical ESP solution that has a few unresolved glitches. The ESP portion of their solution would be more compelling if they could stop peddling their other services like: “Online Surveys” and “Event Marketing” at every opportunity.
The Constant Contact solution is perfect for a computer novice, or even a starter small business who won’t realize that Constant Contact system malfunctions are damaging their brand.

Vertical Response

Vertical Response Summary:

Based in San Francisco CA, this West Coast marketing email service provider startup boasts many accolades for its 50+ employees. Vertical Response provides many other services other than ESP, but they are known that their permission-based email marketing service is their bread and butter.

Reliable. Easy to port data into their system

Expensive. No “all you can eat” program
Poor interface, difficult to use

Vertical Response is a potential solution for your marketing email requirements and it is a decent marketing email service provider, provided you do not intend to bring vast amounts of contact data over.

Jennifer Mosley

Jennifer Mosley has specialized in business analysis since graduating from NYU Stern Business School in 2001. Mosley has become a sought after analyst in the industry. Her writing peers have accused her of spending too much time on Brazilian keratin treatments to tame her unruly locks, but she reminds them that they are misogynist pigs who deserve to be bald. She is currently working on such varied projects as the analysis of the Google corporate breakup and the other important international dilemma between wine or beer shampoo.