Objectives To evaluate experiences and reactions after receiving a mailed, unsolicited human papillomavirus self-sampling kit and identify psychosocial correlates of using kits. Methods Survey participants were underscreened women aged 30–64 who were mailed human papillomavirus kits as part of a pragmatic trial at Kaiser Permanente Washington, a United States integrated health care system. Six months after the mailing, we invited kit returners and non-returners to complete a web survey that measured psychosocial factors (e.g. cervical cancer/human papillomavirus knowledge, attitudes toward screening), experiences, and reactions to kits. We compared responses between kit returners and non-returners. Results Comparing 116 kit returners (272 invited) and 119 non-returners (1083 invited), we found no clinically significant differences in psychosocial factors. Overall, survey respondents showed knowledge gaps in human papillomavirus natural history (82% did not know human papillomavirus infection can clear on its own) and interpreting human papillomavirus test results (37% did not know a human papillomavirus-negative result indicates low cancer risk). Kit returners found kits convenient and easy to use (>90%). The most common reason for non-return was low confidence in ability to correctly use a kit, although many non-returners (49%) indicated that they would consider future use. Women reported low trust in human papillomavirus testing to identify women at high risk for cervical cancer (52% in returners, 42% in non-returners). Conclusions Screening programs could improve uptake and acceptability of human papillomavirus self-sampling through outreach materials that emphasize the high efficacy of human papillomavirus testing for cervical cancer screening and educate patients about how to interpret results.