Incentives are used to increase response proportions to postal questionnaires. Our objective was to compare the response proportions between incentive groups receiving a $1 bill, pen, both and none with a postal questionnaire for a veterinary public health survey conducted among veterinarians in Texas. We mailed questionnaires to a random sample of veterinarians (n=683) from Texas with three types of incentives viz. $1 bill (n=118), pen (n=111), $1 bill with pen (n=114), and questionnaire only (n=340). A total of 303 (44%; 95% confidence interval, CI: 41–48) responses were received with the lowest response proportion of 37% (95% CI: 32–43) in the no incentive group and highest response proportion of 57% (95% CI: 47–66) in $1 bill incentive group. Compared to no incentive, the response proportions were significantly higher (P<0.01) in groups receiving $1 bill, $1 bill with pen, and all incentives combined ($1 bill, a pen or both). The addition of a pen only did not improve response proportion. These findings support the use of $1 bill but not a pen alone as an effective incentive to increase response proportions to a postal questionnaire.