jetpack forms

No, your HTML code will be stripped from the form builder.

Could you let me know what you’d like to achieve? There might be another way to do what you want to do.

Thanks!

You should be able to add that link thanks to the grunion_contact_form_field_html filter:
https://github.com/Automattic/jetpack/blob/3.6.1/modules/contact-form/grunion-contact-form.php#L1863

Here is an example that should show you how to use the filter:
https://gist.github.com/pippercameron/6613780

I hope this helps.

Let me try to give you an example.

In the screenshot below, I’ve added a link to my “Terms” page right before the checkbox:
http://i.wpne.ws/cFQQ

Here is the code I used:

// Add a link to the checkbox label
function jeherve_grunion_link_checkbox_label( $field_html, $field_label, $post_id ) {
	// First, let's make sure we only customize the contact form on a specific page, using the page ID 1370
	if ( ! is_page( '1370' ) ) {
		return $field_html;
	}

	// Then, we'll make sure we only make changes to one label, named "Check the box to agree to the terms"
	if ( 'Check the box to agree to the terms' == $field_label ) {
		$field_html = '<a href="http://google.com">Do you agree to the terms and conditions?</a>' . $field_html;
	}

	return $field_html;
}
add_filter( 'grunion_contact_form_field_html', 'jeherve_grunion_link_checkbox_label', 10, 3 );

You can start from that code, and modify the page ID, the label name, and the link you’d like to use. Once you’ve done so, you can paste the code snippet in your theme’s functions.php file or in a functionality plugin.

I hope this helps.