Our research elicited UK consumers¡¯ willingness-to-accept (WTA) discount in exchange for giving up non-GM food and willingness-to-pay (WTP) premium to purchase non-GM food. Eliciting only WTP does not provide sufficient information for determining substitutability between GM and non-GM food. Results indicate that there is a strong demand for non-GM food in the UK, but a non-negligible segment expressed their willingness to substitute non-GM food with GM version either without discount (12 %) or with discounts (34 %). This result suggests that there is an economic incentive for food industry in Europe to offer GM food to consumers.