The distinct element of a three‐part tariff (3PT), compared with linear pricing (LP) or a two‐part tariff, is its quantity target within which the marginal price is zero. This quantity target instrument enriches the firm's strategy set in dictating the competition to a specific level, even in the absence of a usual price discrimination motive. With general differentiated linear demands, the competitive effect of a 3PT in contrast to LP depends on the degree of substitutability between products: Competition is intensified when two products are more differentiated, yet softened when two products are more substitutable.