Two customer service advisers with Lloyds Bank stole £42,000 from customers, a court was told.
Huddersfield man Adam Lorgat and Saad Hussain from Bradford conned 45 customers while they worked at a call centre in Leeds.
The pair recorded customers’ security details and passed them to others who then made fraudulent telephone calls requesting money to be transferred into other accounts.
Vulnerable people were recruited to accept money into their accounts, including students from Kirklees College, Leeds Crown Court heard.
Cash sums were later withdrawn from cash machines and at banks before being handed over to the fraudsters.
The crimes took place during a three-month period in 2014. Lloyds Bank contacted police after discovering the scam.
Lorgat and Hussain pleaded guilty to fraud by abuse of position.
Lorgat, 24, of Bradford Road, Fartown was jailed for two years, 11 months. Hussain, 26, of Summerlands Grove, Bradford was jailed for two years, five months.
Five other men were jailed for a total of 13 years, nine months for their parts in the conspiracy.
Det Insp Phil Jackson from Leeds District Serious Organised Crime Unit said: “Lorgat and Hussain abused their positions of trust as bank employees to carry out a determined and carefully orchestrated fraud that saw tens of thousands of pounds stolen from customers’ accounts.
“They enlisted the help of the others who recruited a number of vulnerable individuals to give the gang access to the funds they were fraudulently transferring into their accounts.
“Their activities were first flagged up by the bank’s internal security processes and a complex and protracted police investigation followed that has seen these men brought to justice and sentenced to more than 18 years in prison.
“We hope their convictions will send a very clear deterrent message to others who involve themselves in frauds of this nature and highlight the serious penalties they can expect.”