6. Use Large Fonts and Characters Judiciously

Fonts larger than +2 or size 3 (normal) cost you 0.34 points. I don't believe this includes H1, H2, H3 (presumably not), so I'll probably use HTML headers in the future rather than font tags to increase font size.

7. Avoid Suspect Spam Phrases

This list is a long one. I've included it on its own webpage so you can print it out for easy reference -- "Words and Phrases that Trigger Some Spam Filters," Web Marketing Today, 12/3/02. http://www.wilsonweb.com/wmt8/spamfilter_phrases.htm

Does it help to include * or ^ characters in place of vowels? The jury's still out. I suspect that some spam filters are smart enough to detect this ruse, but I'm not sure.

8. Be Careful with Subject Lines

SpamAssassin is particularly interested in subject lines. Here are a few subject lines no-nos to learn from:

Contains "FREE" in CAPS
0.43

Starts with dollar amount
1.10

GUARANTEED
0.62

Starts with "Free"
0.30

Starts with "Hello"
1.58

To: username at front of subject
2.86

Subject includes a question mark or exclamation point
0.10

Subject contains lots of white space
2.64

Subject is all in capitals
0.48

Subject talks about savings
0.41

Subject talks about losing pounds
0.51

Subject is missing
0.34

9. Carefully Word Your Unsubscribe System

It seems ironic that legitimate opt-in e-mailers are penalized for having unsubscription information. But since so many spammers have bogus systems, it is apparently a spam indicator. For example:

List removal information
1.00

Click-to-remove with PHP/ASP action found
0.30

Claims you can be removed from the list
2.70

Claims to listen to some removal request list
1.00

Says: "to be removed, reply via email" or similar
0.45

Header contains exists:X-List-Unsubscribe
1.11


You need to include ways to unsubscribe, of course, but avoid the phrase "click here to..." and substitute something like "use this link to ...." You're especially hurt by using mailto e-mail links with "remove" -- or anything, for that matter -- in the subject. Make sure that the program you are using to unsubscribe people doesn't have "unsubscribe" or "remove" in the URL.

10. Flaunt Being a Newsletter

Fortunately, being a legitimate newsletter lowers your spam score.

Subject contains newsletter header (list)
-0.22

Subject contains newsletter header (news)
-0.62

Subject contains newsletter header (in review)
-1.00

Subject contains a frequency - probable newsletter
-0.73

Subject contains a month name - probable newsletter
-0.48

Subject contains a date
-1.60


Other words and phrases which may help you include a PGP signature, or something about a forgotten password or a registration system.