Is there any way to make an email's subject bold?

Question

I am sending email using C#.NET, for which I am using System.Net.Mail.MailMessage class. I want to make a portion of the email's subject bold. Is there any way to do it?

Answer 1

No, there is no way to format the subject of an email message with font styles, weights, faces, color, etc. It is plain-text only.

It's not a limitation of .NET, rather it's the way email is.

Answer 2

While you have no control over the subject, you could hint to the email clients that a message is important by setting the priority. Depending on the client, it might be highlighted in some way.

eg

message.Priority = MailPriority.High;

Since people abuse this, email clients could very well ignore it. But see if it works for you!

Answer 3

Well actually there's a not-so-pratic way, you'll need to combine characters entities to do so, take a look at this page

http://www.fileformat.info/info/unicode/block/mathematical_alphanumeric_symbols/list.htm

and try some styles here

https://qaz.wtf/u/convert.cgi?text=style+my+subject

Hope it helps.

Answer 4

There is a way - and icons etc - just check your spam for examples... (here is one from today)

From: Diamond Hand Insider <that@your.diamondhandinsider.com>
To: 
Subject: 🔎 𝐁𝐢𝐥𝐥𝐢𝐨𝐧𝐚𝐢𝐫𝐞’𝐬 𝐅𝐢𝐧𝐚𝐧𝐜𝐢𝐚𝐥 𝐃𝐨𝐜𝐬 EXPOSED
Date: Thu, 12 Jan 2023 12:34:36 -0600
List-Unsubscribe: etc

but not sure its a great idea, I think this will make it more likely to flagged as spam. They are using the unicode symbols I believe