Behavioral interventions show potential for promoting increased fruit and vegetable consumption in the general population. However, little is known about their effectiveness or cost-effectiveness among socioeconomically disadvantaged groups, who are less likely to consume adequate fruit and vegetables. This study investigated the effects and costs of a behavior change intervention for increasing fruit and vegetable purchasing and consumption among socioeconomically disadvantaged women. ShopSmart 4 Health was a randomized controlled trial involving a 3-mo retrospective baseline data collection phase [time (T) 0], a 6-mo intervention (T1-T2), and a 6-mo no-intervention follow-up (T3). Socioeconomically disadvantaged women who were primary household shoppers in Melbourne, Australia, were randomly assigned to either a behavior change intervention arm (n = 124) or a control arm (n = 124). Supermarket transaction (sales) data and surveys measured the main outcomes: fruit and vegetable purchases and self-reported fruit and vegetable consumption. An analysis of supermarket transaction data showed no significant intervention effects on vegetable or fruit purchasing at T2 or T3. Participants in the behavior change intervention arm reported consumption of significantly more vegetables during the intervention (T2) than did controls, with smaller intervention effects sustained at 6 mo postintervention (T3). Relative to controls, vegetable consumption increased by ∼0.5 serving · participant(-1) · d(-1) from baseline to T2 and remained 0.28 servings/d higher than baseline at T3 among those who received the intervention. There was no intervention effect on reported fruit consumption. The behavior change intervention cost A$3.10 (in Australian dollars) · increased serving of vegetables(-1) · d(-1)Conclusions: This behavioral intervention increased vegetable consumption among socioeconomically disadvantaged women. However, the lack of observed effects on fruit consumption and on both fruit and vegetable purchasing at intervention stores suggests that further investigation of effective nutrition promotion approaches for this key target group is required. The ShopSmart 4 Health trial was registered at www.isrctn.com as ISRCTN48771770.