Recent research has shown mixed-mode surveys are advantageous for organizations to use in collecting data. Previous research explored web/mail mode effects for four-contact waves. This study explores the effect of web/mail mixed-mode systems over a series of contacts on the customer satisfaction data from the Florida Cooperative Extension Service during 2012-2013. The experimental design involved a group of clients who provided e-mail and mail contact information randomly assigned to two mixed-mode treatment groups and a mail-only control. Demographic and service utilization data were compared to assess response rates and nonresponse bias. Logistic regression showed the treatment groups had similar response rates and nonresponse bias. The fifth contact was statistically significant in increasing response rates but did not reduce nonresponse bias. Future research should continue exploring optimizing the number of contacts in mixed-mode survey methodology.