As the others have been saying, you probably want to limit the width to 600px, just because many email clients will have trouble with larger than that. However

As the others have been saying, you probably want to limit the width to 600px, just because many email clients will have trouble with larger than that. However, we actually don't use tables when it comes to our templates; we apply styles to divs and ps when we flatten the HTML and CSS. Happy to chat further if you're interested!