Beginning in 1970, American troops were withdrawn from border areas where most of the fighting took place and instead redeployed along the coast and interior. While U.S. forces were redeployed, the ARVN took over combat operations throughout the country, with casualties double US casualties in 1969, and more than triple US ones in 1970. In the post-Tet environment, membership in the South Vietnamese Regional Force and Popular Force militias grew, and they were now more capable of providing village security, which the Americans had not accomplished under Westmoreland.

In 1970, Nixon announced the withdrawal of an additional 150,000 American troops, reducing the number of Americans to 265,500. By 1970, Viet Cong forces were no longer southern-majority, as nearly 70% of units were northerners. Between 1969 and 1971 the Viet Cong and some PAVN units had reverted to small unit tactics typical of 1967 and prior instead of nationwide grand offensives. In 1971, Australia and New Zealand withdrew their soldiers and U.S. troop count was further reduced to 196,700, with a deadline to remove another 45,000 troops by February 1972.