Banks make mistakes from time to time, and they are generally quite costly, costing millions or sometimes billions of dollars. Take a look at some of the most bizarre bank mistakes.

Citibank: ‘Biggest Blunder in Banking History’

Citibank inadvertently sent $900 million to Revlon's creditors while serving as a lending intermediary for the troubled cosmetics firm.

KfW: ‘Germany’s Dumbest Bank’

In February 2017, KfW bank transferred roughly 5 billion euros ($5.4 billion) to four banks in error due to a technical fault that repeated single payments many times.

KfW: History Repeating Itself?

During the 2008 financial crisis, KfW wired 320 million euros (roughly $338 million) to the Lehman Brothers business by mistake in September 2008.

Deutsche Bank: ‘Fat Finger Errors’

In April 2018, German investment giant Deutsche Bank inadvertently moved $35 billion to one of its foreign accounts in what was dubbed a "fat finger error."

Santander: A Christmas Miracle?

Last December 25, British bank Santander inadvertently transmitted £130 million (about $175 million) in duplicate payments to its clients.

Mizuho Securities: An Expensive Typo

Mizuho Securities, a Japanese investment banking firm, paid a high price in 2015 after one of its stockbrokers mistyped a critical piece of data.

PayPal’s 92 Quadrillion Mistake

In 2013, the software business delivered $92 quadrillion to a guy called Chris Reynolds in Pennsylvania by mistake. a quadrillion dollar is equal to a thousand trillion

Barclays’ ‘Simple Task Mistake’

Barclays Chairman Higgins revealed this year that the company had suffered a multimillion-dollar trading error” due to a trader making “some mistakes on simple tasks.