<th>

Cf. <td>

Tips

It should be known that a <th> tag has a default formatting on some mail clients and browsers. It's therefore necessary to apply a CSS reset specifying this code:

<tr>
    <th style="font-weight:normal; padding:0px;">
        <p style="font-family:Arial, Helvetica, sans-serif; font-size:12px; color:#000000; text-align:left; line-height:18px;">Content</p>
    </th>
</tr>

Thus, texts won't be automatically in bold, and no internal margin will be present.

A question?