Important: only use tables if they are necessary for your messages design and content. If your content can be displayed using text blocks (or other editor blocks) we recommend that instead.
What the editor keeps and what it changes
When you save, Envoke copies the block's text styling onto every table cell so that Outlook renders the right font and colour. That means:
The block always wins for font family, font size, line height and text colour on the <td> itself. To give a cell its own text colour, wrap the text in a span: <span style="color:#ffffff;">Header</span>.
Your own cell styling is kept: background colours, borders, padding, width, height, vertical alignment, text alignment and white-space.
Classes and any HTML attribute on table elements are kept (width, align, valign, bgcolor, cellpadding, cellspacing, border).
Anything else in a style attribute on <table>, <tr> or <td> is removed when the block is edited.
Tips for reliable rendering, including Outlook desktop
Put row shading on the cells, not the row: <td style="background-color:#f2f2f2;"> or <td bgcolor="#f2f2f2">. Outlook handles <tr> backgrounds inconsistently.
Set the table width as an attribute: <table width="100%">. Outlook ignores percentage widths written in CSS. On phones the editor's responsive styles already force tables to full width.
Put borders on the cells and set border-collapse: collapse; on the table. Borders written on the <table> element itself render unevenly in Outlook.
Use cellpadding or a padding style on each cell for spacing inside cells. Margins on cells are ignored by most email clients.
Avoid <th>, colspan tricks and nested tables where a simple grid will do. Keep column widths consistent between rows.
A starting point
<table width="100%" cellpadding="6" cellspacing="0" style="border-collapse:collapse;">
<tr>
<td style="background-color:#4d4d4d; border:1px solid #cccccc;"><strong><span style="color:#ffffff;">Item</span></strong></td>
<td style="background-color:#4d4d4d; border:1px solid #cccccc;"><strong><span style="color:#ffffff;">Amount</span></strong></td>
</tr>
<tr>
<td style="border:1px solid #cccccc;">Annual membership</td>
<td style="border:1px solid #cccccc;" align="right">$120.00</td>
</tr>
<tr>
<td style="background-color:#f2f2f2; border:1px solid #cccccc;">Workshop registration</td>
<td style="background-color:#f2f2f2; border:1px solid #cccccc;" align="right">$45.00</td>
</tr>
</table>
One thing to know about cell backgrounds
A cell background that is exactly the same colour as the block background is treated as inherited and dropped when the message loads. This is invisible, but if you later change the block background those cells will follow it instead of staying the old colour. Pick a slightly different shade if a cell must keep a fixed colour.