• by Morgan Stewart , July 18, 2012

Testing should go well beyond the subject line. According to eConsultancy’s 2012 Email Marketing Industry Census, 66% of email marketers test subject lines regularly. Second on the list is time/day of week, at 44%, and it goes down significantly from there. Only 16% of marketers test email frequency.

As I talk to marketers running email programs, it's clear they've adopted the “test, test, test” mantra. Marketers know they should test, but it’s easy to get in a rut testing the same things over and over again (e.g., subject lines).

The following is a personal list compiled and modified over the past 10 years. Not all of these will be relevant to your program. And some of them are more likely to have a significant impact on performance than others. Take a look and see if any of these present new opportunities for you to test and improve your email program.

1. Sender Names
2. From Address
3. Name Personalization
4. Gender Segmentation
5. Geographic Segmentation
6. Other Demographic Segmentation (Income, Marital Status, Children, etc.)
7. Occupation
8. Prospect vs. Customer
9. Loyal Customer vs. One-Time Customer
10. Last Open / Click Date
11. Last Store Visit Date
12. Intro Text—Content
13. Intro Text—Copy Style
14. Body Text—Content
15. Body Text—Copy Style
16. Closing Text—Content
17. Closing Text—Style
18. Header Image—Present / Not Present
19. Header Image—Style
20. Home City / State / Airport / Etc.
21. Store / Branch / Office Location
22. Maps
23. Sales Representative
24. Travel Destination
25. Travel Time
26. Recent Transactions / History
27. Overt Recommendations (i.e.,  “You may also like…”)
28. Subtle Recommendations (i.e., personalized, but not overtly)
29. Weather
30. Price Brackets
31. Whitepapers
32. Organized vs. Unorganized Product / Article / Content Categories
33. Ad Unit Placement / Configuration
34. Ad Unit Sizes
35. Referral Offers
36. HTML vs. Text-Only
37. Mobile-First Layout
38. Responsive Layout (i.e., Optimized to Screen Size)
39. Animated GIFs
40. Embedded Video
41. Ratings and Reviews
42. Price Points
43. Price Strikeouts
44. Font Type
45. Font Colors
46. Headlines
47. Sub-headlines
48. Signatures
49. Personalities (e.g., Editor, Author, Sales Rep, Executive)
50. Location Shots
51. Lifestyle Shots
52. Product Shots
53. Links vs. Buttons
54. Link / Button Placement
55. Link / Button Copy / Call-to-Action
56. Icons
57. Bullet-Proof Buttons
58. Postcard Layouts
59. Newsletter Layouts
60. Horizontal Scrolling
61. Event Focus
62. Polls
63. Privacy Policy Language
64. Unsubscribe Copy
65. Opt-Down
66. Heavy vs. Light Imagery
67. Long Copy vs. Short Copy
68. Phone Numbers (e.g., Click-to-Call)
69. Social Media Buttons
70. Facebook “Like” Teaser Copy
71. Facebook Comments / Testimonials
72. Facebook Friends that “Like” Something
73. Follower Tweets / Testimonials
74. Pins
75. Local Foursquare Mayor
76. Taglines
77. Press Mentions
78. Limited Time
79. Last Chance
80. Number of Products / Articles / Etc.
81. Teaser Copy Length
82. Social Proof (e.g., Number of Likes, Tweets, Views, Comments, Etc.)
83. Exclusive Email Offers
84. Editors Pick
85. Staff Favorites
86. Customer Favorites
87. Background Color
88. Background Images
89. Landing Pages
90. Preheader Text
91. Navigation Bars
92. Search Forms
93. Free Shipping
94. Percent Off vs. Money Off
95. Print Options
96. Versioning by ISP
97. Add to Address Book
98. Time of Day
99. Day of Week

100.Delivery by Timezone

101.And yes… Subject Lines

I welcome any and all additions you would like to add. My hope is merely that this list will help stir your creative juices. If you add all the content specific to your products and services, I imagine you can quickly get the list up to 150.

There is truly no end to the things we can test in email; it’s likely there are changes you could make today that would increase your performance by double digits or more. Why limit testing to a few small things in hopes of improving performance by a percentage point here and there? Break out of the rut and dream big!