We investigate the effects of a range of different types of anchor on WTP and WTA valuations of familiar consumer products, elicited through individuals’ buying or selling decisions at given prices. We find anchoring effects only when the anchor value is framed as a plausible price for the good for which the individual is a potential buyer or seller. Anchoring effects are stronger for WTA than for WTP. We conclude that anchoring effects can affect market behaviour, but that not all anchors are effective.