Email with text/html but without plain/text

Question

I am writing a software to send transactional emails and I had several issues when it comes to sending emails with plain/text and text/html.

I know that it is not advised to send emails without plain/text portion but I am really considering it.

So, here is my question. Nowadays, is it a concern if I send emails with text/html but without plain/text portion?

I have tested it with Gmail, Hotmail, and Microsoft Outlook (via Microsoft Exchange) and it worked very well so far.

Thanks,

Answer 1

Well, old devices may not be able to display text-only format properly as mentioned by samanthasquered. But, in my case mail-filters (spam filters or any filter created manually as mentioned by Mike W) would be a bigger concern.

Here is the best reference I could find about this topic: http://blog.hubspot.com/blog/tabid/6307/bid/32643/Why-Marketers-Must-Optimize-Emails-for-HTML-AND-Plain-Text-Infographic.aspx

Thanks,