Daniel Kaye, 29, is accused of using the botnet to attack Barclays Bank and Lloyds Group and blackmail them.
He is due to appear at Westminster Magistrates Court in London on Thursday, August 31, where he faces nine counts under the Computer Misuse Act, two counts of blackmail and one count of possession of criminal property.
Daniel Kaye has been extradited from Germany to face charges in the UK of launching cyber attacks on Lloyds and Barclays in Jan this year— Financial Consulting (@BTG_FC) 31 August 2017
"The investigation leading to these charges was complex and crossed borders. Our cyber crime officers have analysed reams of data on the way," said the NCA's senior operations manager, Luke Wyllie.
"Cyber crime is not victimless and we are determined to bring suspects before the courts," he added.
Lloyds' online services were disrupted by the attack in January this year, while Barclays fended off a cyber assault a few days later.
The same botnet was allegedly used in November against Lonestar MTN, Liberia's biggest internet provider.
Liberia, one of Africa's poorest countries, is particularly vulnerable to cyberattacks because it depends on a single ACE fiber internet cable, which it shares with other West African countries.
A botnet is created when computers are infected with malware which allows them to be controlled remotely.
They are often used, as in this case, to launch distributed denial of service (DDoS) attacks, which overwhelm an internet provider's servers, sending it offline.