Will One More Dollar Help? The Effect of Sequential Incentives on Survey Participation and Costs in a Concurrent Mixed-mode Survey

Prepaid monetary incentives increase response rates in surveys. Whether offering a second monetary incentive to nonrespondents in web-and-mail surveys increases response rates and improves sample composition is relatively unexplored. This article examines an experiment in a general population probability survey in which nonrespondents were randomly assigned to receive $0, $1, $2, or $5 in a later mailing after receiving an initial $1 in the first mailing. Response rates increased for the sequential incentive conditions, but at a decreasing rate. There was no consistent difference in sample composition across the sequential incentive levels, although younger and more mobile adults were more likely to participate with sequential incentives. Costs per completion were similar for the $1 and $2 conditions ($51 and $54, respectively), but about $83 per complete for the $5 condition. Survey practitioners may consider using a $1 or $2 sequential incentive to increase response rates at a reasonable cost.