The one-sample fecal immunochemical test (FIT) is gaining popularity for colorectal cancer (CRC) screening of average-risk people. However, uptake and annual use remain suboptimal. In 2013, we mailed questionnaires to three groups of nonHispanic White, Black, and Latino Kaiser Permanente Northern California (KPNC) members ages 52-76 who received FIT kits in 2010-2012: Continuers did the FIT all 3 years; Converts in 2012, but not 2010 or 2011; and Nonusers in none of the 3 years. The questionnaires covered social influences, perceived CRC risk, reasons for using (Continuers, Converts) or avoiding using (Nonusers) the FIT, and recommendations for improving the kit. Continuers (n?=?607, response rate 67.5%), Converts (n?=?317, response rate 35.6%), and Nonusers (n?=?215, response rate 21.1%) did not differ in perceived risk or family history of CRC, but Nonusers were less likely than Continuers and Converts to know someone who had polyps or CRC. Continuers, Converts, and Nonusers did not differ in social network encouragement of CRC screening, but did differ in believing that it was very important that they be screened (88.3%, 68.4%, 47.7%) and that their medical team thought it very important that they be screened (88.6%, 79.9%, 53.9%). Approximately half of Continuers and Converts completed the FIT to please their doctor. Converts were less likely than Continuers to use the FIT to “make sure they were OK” (53.7% vs. 72.6%) or “protect their health” (46.1% vs. 76.4%). Nearly half of Converts completed the FIT out of guilt. Approximately half of FIT kit users suggested adding a disposable glove, extra paper, and wider-mouth tube to the kit. Nonusers’ reasons for not using the FIT included discomfort, disgust, or embarrassment (59.6%); thinking it unnecessary (32.9%); fatalism/fear (15.5%); and thinking it too difficult to use (14.5%), but <10% did not want CRC screening at all. Nonusers and irregular users of the FIT are less intrinsically motivated to get CRC screening than long-term users and more averse to preparing their stool sample. Changes to the FIT kit to address discomfort and difficulty factors might improve uptake and continued use.