Do forms work in HTML emails?

Posted by Mark Wyner on November 7, 2007

Over the years we've received loads of inquiries about the use of forms in emails, such as newsletter subscribe forms, event registration and surveys. So we decided to run some tests to get to the bottom of just how well forms are supported in all the major email environments.

Is it okay to use forms in emails? It’s not the best idea. But what do you say when your client asks you to put one in an email? You can either tell them “no” for reasons which may not make sense to them, or you can back up your defiance with some hard evidence.

The short of it is that email clients consider email forms to be a security risk. While some email clients simply warn you of potential danger, others outright disable the forms. So if your client wants to send out a form, they should know that most of their recipients will never be able to use it. And for those who can, they’ll think twice about submitting data when they see a warning from their email client.

Results Summary

Common email clients share a propensity to distrust forms in email messages. But they differed greatly in how they handled the intruding forms. Following are some notable oddities.

External data submission

Upon submitting a form in many webmail clients, a JavaScript alert announces that the form is submitting data to an external page and asks if you want to continue:

Scam alerts

Thunderbird recognizes that the form may be malicious but doesn’t strip its functionality. Instead, it warns you of potential danger:

Odd behavior

Windows Live Hotmail shows the form. However, the form functions in an odd way; and certainly not correctly. If the form is submitted by keying the “return” key, the page is refreshed but no data is sent and the process is not completed. If the form is submitted by clicking the submit button, nothing happens. Outlook 2007 also exhibits some unique behavior in that it custom renders the form. Inputs are replaced with brackets and the submit button is replaced with the button’s value enveloped in brackets. So it's a plain-text version of what the form would look like, even though the HTML is being displayed.

Complete Results

How Forms Perform in HTML Emails
Client	Form is displayed	Form is functional
.Mac
Yahoo! Mail
Yahoo! Mail Classic
AOL Webmail
Gmail
Windows Live Hotmail
Apple Mail
Thunderbird
Penelope (Eudora 8)
Outlook 2007
Outlook 2003
Outlook Express
Windows Live Mail
Lotus Notes 8
Entourage

The Recommendation

Given the sporadic support for forms in emails, we recommend linking to a form on a website in an email rather than embedding it therein. This is the safest, most reliable solution to pairing an email message with a form. More people will see it and be able to use it, and as a result participation will increase.

7 comments so far

Stormy

wrote on November 8, 2007 2:26 AM

Hmm, have to differ with at least one of your results here I'm afraid, as we have received and submitted forms using Outlook 2003 SP2, and it appeared to function fine.

That aside, I completely agree on leaving forms out of email. If an email is generating enough interest that someone fills in a form, then it is enough for them to click a link to a webpage before they fill it out.

Mark Wyner

wrote on November 8, 2007 6:26 AM

Thanks for sharing, Stormy. It's interesting that we experienced different results because we, too, tested Outlook 2003 on XP with SP2. Maybe the types of forms we used differ?

We probably should have pointed out that we tested the POST which performed very poorly, and then proceeded with a GET form which worked much better. Our chart exhibits results from the latter. Also, our form comprised a single text input with a button. Very simple to see if the most basic form would function.

All said, even if some forms function in Outlook 2003 they continue to be unreliable in many other clients. But know that your feedback is still valuable and we appreciate it very much.

Danny Foo

wrote on November 9, 2007 3:26 PM

I'm curious, by form does it also mean the polls some people include in their newsletters?

I've always been wondering how they achieved this. :S

Dave Greiner

wrote on November 9, 2007 6:06 PM

Danny, yes, this refers to any kind of form element in emails, including polls and surveys. Basically, they are very hit and miss and not recommended.

Jonathan Sweet

wrote on November 10, 2007 2:22 AM

Something that we've noticed is that forms work in Outlook (pre 2007), but not in the preview pane (they won't post to the server).

Sully

wrote on November 17, 2007 12:19 PM

The presumption that participation will increase by using a landing page is open to debate. Users are lazy -- make them click, and that's another commitment. If it's possible to present simple survey queries in an e-mail, you'd likely see more responses. After all, they've already opened the e-mail -- all they have to do is tick a few boxes, or fill out some info, and click. But if they have to take another step, they might be more likely to abandon.

Mathew Patterson

wrote on November 19, 2007 6:12 PM

You are right Sully - it is an extra click, and you would expect to lose some people because of that. Unfortunately though, forms just don't reliably work in email, and it is worse for someone to fill out a form and then see it fail.

The raw number of participants may fall by having a landing page, but the number of successful forms lodged would be expected to increase.