Increase conversions through MailChimp’s pre-filled data forms

When it comes to marketing online, reducing friction in the experience is the name of the game. So, when you need to collect important data to record a registration or make a sale, one way to increase the odds of completing the transaction and closing the deal is to use pre-populated form data, instead of asking customers to fill out basic data over and over again. This is where the form contains their contact info, based on data they input previously, so that they don’t have to enter it again.

The benefits of pre-filled, or pre-populated forms

According to Privy, on their blog with each field of information you require, you lose fifty percent of your audience, so that the more detailed a form is, the fewer visitors are likely to input all of the required data. Conversely, they claim a more than 30% conversion rate increase with pre-populated forms.

Since the online experience is an exercise in instant gratification, anything that slows it down will necessarily decrease successful responses. People simply cannot be bothered. If it costs them more hassle, they will often opt out of completing the transaction. Then, there are privacy concerns that make some leery of adding information and having to stop and decide may tip the scales against you.

  • Prepopulated forms can save a lot of time, especially for returning visitors that have filled out forms on your site before
  • Some form builder software will pre-populate data from any form built on their system, whether it was on your site or not
  • Since you can pre-populate information that was previously collected, you can ask for additional data with each form

Streamlining the user experience just takes some of the decision-making and work out of saying yes to your call to action or offer. There are some technical hurdles in most cases to make this work,  but it can be done in most form platforms if you’re willing to take the time to find out what it takes and  thoroughly test your customised forms before launching them to customers.

Why you might want to prepopulate forms on your site

The more data you can collect on each lead capture, the more opportunities you have to target your offers to that specific prospect. By collecting multiple ways to contact them, they become more available, and some contact information, such as street address, also helps with marketing tasks like collecting demographics.

Formstack had this to share on their blog

If your form has too many fields, even the most motivated users may not make it all the way to the end. Case in point:

  • The average order form contains 22 fields and has a conversion rate of 9%
  • The average registration form contains 15 fields and has a conversion rate of 11%
  • The average lead generation form contains 11 fields and has a conversion rate of 17%

Notice a trend? Fewer fields to fill out = higher conversion rates.

Getting the most data, a bite at a time

Since increased fields can mean lowered conversions, why not increase the data incrementally? If your initial contact is simple, like a name and email, you have a much higher likelihood of an initial conversion, which, as we’ve discussed in previous posts, serves to qualify the lead by moving them closer to understanding your company, products and services.

If you ask for one or two more pieces of data with each successive form, while prepopulating information previously gathered, your ask seems smaller. They want your content and giving up one more piece of data to a company that has already given them valuable content that helped them in their personal pursuits, is a much easier choice to make than filling out a complete, 25 field form.

  • Prospect data files can be built over time, one or two pieces of information at a time
  • With each new piece of information, you can better target the offers you present
  • You are also building trust as you qualify your lead, bringing them further into your marketing funnel

What about the technical part?

Most form building platforms allow for prepopulated forms. In some systems, it is simply a matter of selecting a prepopulating option on your form, then choosing which fields to collect. Apps like Optimize Press, Privy, Instapage and Gravity Forms provide detailed instructions for making the required changes within their systems. In other form builders, the pre-population is based on an emailed link, customized to lead to the prepopulated form.

You’ll need data from your form building software, including the field tags for each part of the form you want to prepopulate. Prepopulation can be done two ways, it can fill out the information for every form visitor (such as pre-checking the newsletter sign up box) or customize data that was previously collected on other forms, such as name and address. For Mailchimp users, it is a matter of using a plugin and making a few small changes to your HTML.

Prepopulating forms in Mailchimp

There are two methods in Mailchimp, one is automatic, the other requires a hack. Lead Pages offers a pre-population feature that integrates with Mailchimp. You’ll need to sign up for  a Lead Pages account to access their software.

If you don’t have the budget for a new tool, or prefer the hack method, first find the full URL of your signup form.

Like this:

The U and ID entries are defining your Mailchimp form’s address.

Inside the source code of your signup form, locate the input elements in the HTML form that you want to prepopulate. They are labelled with the term “MERGE_” with _ being a number representing the individual field of the form. Following these labels find field names, such as “First Name” or “Email Address” and select the ones you want to prepopulate.

By adding these HTML tags to the end of your form URL, you can choose fields and prepopulate them with set text. For example if MERGE1 was the label for “First Name” your URL would look like this:


With Bob representing the name of the user. By experimenting with this, you can prepopulate as much of the form as you have information for.

So, there you have it. Let us know how your pre-population works out. Find new tricks, share them and be sure to watch for more in our continued series on automating your marketing with WordPress and Mailchimp

Mike Killen

Mike is the world's #1 sales coach for marketing funnel builders. He helps funnel builders sell marketing funnels to their customers. He is the author of From Single To Scale; How single-person, small and micro-businesses can scale their business to profit. You can find him on Twitter @mike_killen.