What matters and what does not.
WHAT MATTERS LESS THAN PEOPLE THINK
Specific words Exclamation marks Capital letters
Those are minor factors in modern filtering.
WHAT MATTERS MORE
Authentication Reputation Engagement
WHAT CAN STILL AFFECT DELIVERY
A message that is entirely one image Links to domains with poor reputation Misleading subject lines Hidden text Excessive links
THE IMAGE-ONLY POINT
A message with no text and one image resembles spam.
Include real text.
LINKS
Link to your own domain where possible.
Links to shortened or unknown domains are treated with suspicion.
THE SUBJECT LINE
Should describe the content accurately.
Misleading subjects produce complaints, which is what actually damages you.
FORMATTING
Plain and readable. Elaborate design is not required and frequently renders poorly.
WHAT TO INCLUDE
A plain text version alongside any formatted version A working unsubscribe link Your business identity
WHAT TO TEST
How it renders in several clients.
