Getting Started with the Constant Contact AppConnect APIs


What does Constant Contact Mean when we say...


               Contact – Basically, a unique email address and its related information

               List – A collection of contacts, used for sending campaigns, like a Distribution List

               Campaign – An email and its associated information

               Events – An event and its associated information

               Reports - “What happened” for a Contact or Campaign, like Opens, Clicks and Bounces.  Our users call this

                                 “Reporting Data” or “Reports”


What is the AppConnect API?

The Constant Contact AppConnect API is a RESTful API used to access account information for Constant Contact Accounts.  Using our APIs, you can link your application or website to Constant Contact without having your users log into Constant Contact.  This can be used to send and receive any information that is available through our APIs. 


Why Constant Contact?


With so many applications to integrate with, you may be wondering why integrate with Constant Contact?  There are a couple of reasons.  With over 400,000 paying customers, chances are some of your customers are already using us. Integrating with us makes those customers happier and they’ll end up being customers of yours longer. 

Even if your customers aren’t already using Constant Contact, they need marketing tools and communications tools.  Integrating with the leading Email Marketing provider is a great way to provide those extra features your users are looking for.

What do you need to know to get started?


First, get familiar with the APIs. A good place to start is the API Quick Reference, which gives you a brief technical overview of the most commonly used APIs.


All of our APIs require you to have an API Key.  The API key is a unique identifier for a Developer, not a customer, and we recommend having one API Key for each integration you build.  So if you have two software platforms and you integrate both, you should create two API keys.  To create an API Key, all you need is a Constant Contact account (trials work!) and fill out our API Key request form.


The API Key is used as part of every request to ensure that a valid application is making the request.  It is combined with the Username of the account that is making the request in the following format:




You can try to access your own account in this way by opening up a web browser and using the following URI.  Simply enter your Username in the format above and your Constant Contact Password.


Note: Remember to replace anything in curly brackets {} with your personal information! 




Depending on your language of choice we determine how to enter these credentials.  We recommend having the API Key hard coded into your integration so users don’t even know it exists.

Things to keep in mind when designing your Integration

The most successful integrations with Constant Contact are ones that the user doesn’t realize are integrations.  When the user doesn’t know where your application ends and Constant Contact begins, they will be much more likely to use them both and think of them as “one” solution.  To do this, here are some helpful points that can really improve usability:

  • If you have some sort of “Contact Record”, keep the information between Constant Contact and your record up to date.  You can query us to see what has been updated recently and use this to keep both databases synced! 
  • You may want to add a new field for “Opted out from Email Marketing” and keep your unsubscribes synced.  Remember, they’re still your customer’s customer even if they don’t want to receive marketing!
  • When doing things such as importing Contacts or creating Campaigns, let the user name List associated with this activity or pick from one of their existing lists.  This is especially important for importing large numbers of Contacts, customers hate system generated names! 
  • When updating a list, it’s a great feature to give the option to clear the list first.
  • Remember to have a settings area where a customer can add or update their Constant Contact Username and Password.  Customers change these often and need an easy way to update it.
  • There will probably be times when your customers send us data we can’t accept or that is incorrect.  We try to be explicit about why we can’t process it or what the error was.  It’s good to give friendly error messages to your customers when this happens so they can fix the problem.  To make things easier, we supply you with a full list of errors.

Common Integration Points


  • Contact Syncing – Contacts will often update their information or preferences through Constant Contact. Pulling that information back to your system is easy and a great way to keep all your information updated.
  • List Segmentation/Management – Chances are, your application has a bigger picture of your customer’s Contact data than Constant Contact.  You already can leverage that to filter, sort and query in a variety of ways.  A great integration point is to allow your Customers to send any of those powerful segmentation results directly to Constant Contact.  It’s easy to send us up to 20,000 Contacts per request!
  • Reporting Data – We provide our customers with a variety of reporting data such as Opens, Bounces, Clicks, etc.  CRMs can make creative use of this data by creating business decisions such as sales follow ups, enhanced customer profiles, the list is as long as you are creative.  Pulling Reporting data back and building out Contact profiles can really add value to your application.
  • Mobile/Social Media Syncing – Your application may have mobile or social portions.  Those features are great and a logical extension of them is to pull that data back into customers Email Marketing Lists.  Having the ability to manage subscriptions and profiles in your application is a great value add for any Mobile/Social application.

Quick Start Resources

  • Sample Code Libraries – Constant Contact has created libraries for some of the most popular languages today, including: PHP5.1, C#.NET 2.0+ and ColdFusion 9.0.
  • 3rd Party Resources – In addition, there are many open source libraries available from users of the Constant Contact AppConnect API who were kind enough to publish them for use by others, including: Java, Python, PHP4 and Ruby