Avoid The Spam Filter: 9 Subject Line Tips

Spam filters can be tricky to avoid, but if you follow email marketing best practices you’ll usually avoid being placed in the spam folder.

In their recent article on email marketing mistakes, the Email Experience Council highlighted nine things about your subject line that may trigger spam filters:

1) Percent of Capital Letters
Having too many capital letters compared to lowercase letters.

2) Repeating Capital Letters
Having too many capital letters in a row.

3) Gaps In Between Letters
Including words with gaps in between letters (ex. s*a*l*e).

4) Repetition
Including repeating letters and/or symbols.

5) Too Many Special Characters
Overusing special characters like $,#,%, etc.

6) Too Much Punctuation
Overusing punctuation marks.

7) Word/Space Ratio
Using too many blank spaces.

8) First Character Is Special
Starting your subject line with a special character.

9) First Word Is Spammy
Starting your subject line with a common spam word.