An experimental study of the effect of typeface on response rates in direct mail solicitations

For years, the direct marketing industry has relied upon typewriter typefaces as a design element of direct mail letters. The opinion of leading direct mail practitioners is that typewritten-looking letters are more "personal." However, typewriter typefaces have been shown by researchers to be less legible than many other typefaces. This study examines the effect of typeface on response rates in direct mail solicitations. A split-run of 2,725 pieces was mailed to members of the Knoxville Zoo promoting the zoo's Animal Adoption Program. Half of the members received a letter with the typeface Courier (a typewriter typeface) as the control design, while the other half received a letter with the typeface Garamond as the test design. All other elements of the package were the same. The mailing was divided equally across ZIP codes to guard against socio-economic bias of certain geographic areas. Twenty-nine responses were received by the Knoxville Zoo. Twenty were from recipients of the test typeface, Garamond, and nine were from recipients of the control typeface. Courier. While there was no statistically significant difference between Garamond and Courier in either number of responses or average donations, the practical results indicate that typeface is an element of direct mail packages that should be tested.