Low-carbon cities and smart cities are important policy tools for achieving China's "dual-carbon" goal. It is of great practical significance to explore the choice of carbon emission reduction technologies for enterprises under different pilot policies, in order to save production costs and enhance the effectiveness of enterprise emission reduction. Based on this, the study takes profit maximization as the goal, and includes only cleaner production technologies and end-of-pipe technologies in carbon emission reduction technologies, constructs a production function based on Hicks' neutral technology, and analyses the carbon reduction technology selection strategies of enterprises under the three types of pilot policies. Further, the Hansen threshold panel model is applied to verify the scientific validity of this technology selection mechanism. It is found that the selection of cleaner production technologies and end-of-pipe technologies in different pilot policies is based on the ratio of end-of-pipe technology inputs to outputs. Specifically: (1) If this ratio is at (0, 0.5), in low carbon cities, enterprises choose lower cost end-of-pipe technologies; in smart cities, enterprises lack the willingness to invest in carbon emission reduction technologies; and in dual-pilot cities, enterprises use both end-of-pipe technologies and cleaner production technologies to reduce carbon emissions. (2) If this ratio is at (0.5, 1), enterprises in all three types of pilot cities choose lower-cost source management technologies to reduce carbon. (3) The results of the heterogeneity analysis show that under the constraint of production cost, non-state-owned enterprises, old enterprises and enterprises in high-carbon industries lack the incentive to increase their investment in carbon reduction technologies. Therefore, governments at all levels should guide these three types of enterprises to enter the carbon trading market, and stimulate the initiative of low-carbon technological innovation of these three types of enterprises through policy subsidies, high-tech enterprise incubation, and the promotion of carbon emission reduction source-governance technologies, so as to ultimately achieve the decline of the total amount of carbon emissions at the smallest cost of carbon emission reduction.