A complementary metal oxide semiconductor (CMOS) vertical transistor structure with closely spaced p-type and n-type vertical field effect transistors (FETs) is provided. After forming a dielectric material portion contacting a proximal sidewall of a first semiconductor fin for formation of a p-type vertical FET and a proximal sidewall of a second semiconductor fin for formation of an n-type vertical FET, a first gate structure is formed contacting a distal sidewall of the first semiconductor fin, and a second gate structure is formed contacting a distal sidewall of the second semiconductor fin. Because no gate structures are formed between the first and second semiconductor fins, the p-type vertical FET is spaced from the n-type FET only by the dielectric material portion.