The perceived benefit of return of individual research results (IRRs) in accordance to participants' preferences in genomic biobank research is unclear. We developed an online preference-setting tool for return of IRRs based on the preventability and severity of a condition, which included an opt-out option for IRRs for mental illness, developmental disorders, childhood-onset degenerative conditions, and adult-onset conditions. Parents of patients <18 years of age at Boston Children's Hospital were randomized to the hypothetical scenario that their child was enrolled in one of four biobanks with different policies for IRRs to receive (a) "None," (b) "All," (c) "Binary"--choice to receive all or none, and (d) "Granular"--use the preference-setting tool to choose categories of IRRs. Parents were given a hypothetical IRRs report for their child. The survey was sent to 11,391 parents and completed by 2,718. The Granular group was the most satisfied with the process, biobank, and hypothetical IRRs received. The None group was least satisfied and least likely to agree that the biobank was beneficial (p < .001). The response to the statement that the biobank was harmful was not different between groups. Our data suggest that the ability to designate preferences leads to greater satisfaction and may increase biobank participation.