The United States was sending more troops to the encircled capital to help evacuate its civilians after the Taliban's lightning advances brought the Islamist group to the door of Kabul in a matter of days. Just last week, a U.S. intelligence estimate said Kabul could hold out for at least three months.
The fall of Jalalabad has also given the Taliban control of a road leading to the Pakistan city of Peshawar, one of the main highways into landlocked Afghanistan.
It followed the Taliban's seizure of the northern city of Mazar-i-Sharif late on Saturday, also with little fighting.
"There are no clashes taking place right now in Jalalabad because the governor has surrendered to the Taliban," a Jalalabad-based Afghan official told Reuters. "Allowing passage to the Taliban was the only way to save civilian lives."
A second security official in the city said the Taliban had agreed to give safe passage to government officials and security forces while they leave Jalalabad.
The decision to surrender was taken to avoid "casualties and destruction", the person added.