Unfortunately, iframes aren’t currently supported by most email providers and iframes typically don’t work in email.

This is because email doesn’t function the same as a web page. A web page is “live,” meaning it can be viewed by anyone who has access to the web page URL, and when content is changed by the owner, all the web page viewers will see those changes. But emails are stored in your secure, password-protected inbox, and the code in an email doesn’t change. Because an iframe is importing content from another website, there are two reasons it won’t work well in an email:

1. The “passive” email content doesn’t change and isn’t “live,” so it wouldn’t interact well with the content of an iframe, which can change over time.
2. Because iframes load content from an external website, there are large security concerns. Iframes could easily be used to expose your computer to viruses as soon as you opened an email containing one.

Because of those security concerns, most email service providers (Gmail, Yahoo, etc.) won’t allow iframe content in emails and they automatically block it. So when you try to use aiframe in an email and it doesn’t work, it’s actually because of the email provider.

The best way around this is to copy your form landing page and include this in emails, instead of trying to embed the iframe. You can also take a “snapshot” image of your actual form, insert the image into your email, and link the image to your form URL for a more visually pleasing method.

Here is current list of email providers and their support for iframes: