Background: The decoy effect is the phenomenon where the introduction of a third choice to a decision dyad changes the distribution of preferences between options. Objectives: Examine whether this effect exists in alcohol purchasing decisions and whether testing context impacts this. Method: Fiftytwo participants tested in either a bar or library context and were asked to choose one of a series of beer and water deals presented for timed intervals. In some cases, two options were presented (with similar attractiveness) and in other cases a third, less preferable, decoy option was added. Results: A basic decoy effect in both alcohol and water purchasing decisions. Specifically, there were reductions in the selection of both the original options when the decoy was added into choice dyads. A significant interaction demonstrated in the bar context there was a significant difference such that there was a slight increase in participants selecting the most cost effective option when the decoy was added, and a simultaneous decrease in those choosing the moderately cost effective option. There were no such differences observed in the library condition. Conclusion: The same product may be perceived differently across contexts and, as such, consumers in a pub environment may be particularly vulnerable to the decoy effect.