The blast took place at 8:35am (0405 GMT) near the Kabul Bank branch in Kunduz province, killing the bank's security guard and four others including civilians and members of Afghanistan's ruling Taliban movement, police said.
Seven people were wounded, provincial police spokesman Jumma Uddin Khakasr added.
He did not say who was believed to be behind the attack and no group has claimed responsibility so far.
Militants from the Afghan chapters of Islamic State have waged an insurgency against the Taliban since they returned to power in 2021.
Taliban authorities say they have mostly crushed the group, even as it continues to carry out attacks in Afghanistan.
A suicide bomber killed five people including Taliban security forces on Tuesday in an explosion outside a bank in northern Afghanistan, police said.
Seven people were also wounded in the attack which targeted a queue of people waiting to collect their salaries from a bank in the city of Kunduz, the capital of Kunduz province.
“A suicide bomber, who had improvised explosive devices, detonated himself,” said Jumadin Khaksar, police spokesman for Kunduz province.
He said civilians, civil servants and members of the Taliban security forces were among those killed.
“The Kunduz Province Police Command is working with relevant organisations to find the perpetrators of the incident and bring them to justice.”
In March last year, a suicide bomber killed at least three people when he detonated a bomb outside a bank in the southern city of Kandahar, in an attack claimed by the regional chapter of the Islamic State (IS).
There was no immediate claim of responsibility for Tuesday’s attack.
The number of bomb blasts and suicide attacks in Afghanistan has markedly declined since the Taliban ended their insurgency after seizing power in August 2021, ousting the US-backed government.
However, a number of armed groups — including IS — remain a threat.
