In a highly secure warehouse on a back street in London, high speed note sorting machines whir through thousands of pounds every minute. There are two of these machines in the high security building, which can count, authenticate and sort 33 notes per second through a complex array of sensors and fast moving belts. Inside, they look like a mini, note-sized roller coaster.

The facility, G4S’s flagship cash centre, is at the heart of a historic change in currency. On February 20, 2020, the new £20 note was officially released. It is the most secure banknote ever issued by the Bank of England, with two see-through windows and a hologram image that flips between “twenty” and “pounds”when the note is tilted. These features make it incredibly difficult to copy. An image of celebrated British artist Joseph Mallord William “JMW” Turner is on one side.

The new note follows the release of a polymer £5, bearing the likeness of Winston Churchill, and the Jane Austen £10. A new £50 note featuring Alan Turing will be released by the end of 2021.

Over the coming months, G4S’s role transporting cash for major retailers and the vast majority of UK bank branches means its high speed note sorting machines - including those at the cash centre in London - will help the Bank of England remove a significant number of the more than two billion cotton £20 notes from circulation. G4S handles 65 percent of all notes moved between cash centres, banks and retailers, as well as 60 percent of wholesale cash between the Bank of England and cash centres. In 2019 alone, G4S’s UK cash business moved £120bn in £20 notes. 

“They’ll be vital in identifying and sorting out the old notes. The old £20s will be wrapped in blocks of £50,000. They’re tightly packed, sealed and stored in metal cages in the cash centre’s vault.”

The replacement of two billion notes will be the biggest cash replacement in UK history. While cotton notes will remain legal tender for months, the process to remove them begins immediately. There are currently 3.8 billion notes in the UK, worth about £70bn in total.

G4S’s UK Cash Solutions business is one of four members of the Note Circulation Scheme (NCS), a trusted group organised by the Bank of England to ensure notes are authentic and high quality. In 2019, the NCS processed £93bn.

Beginning in mid-2019, technicians steadily updated G4S’s note sorting machines so they would recognise the new polymer note and simultaneously sift out the old. This was rigorously tested in the lead up to the launch day.

The Polymer Project Manager for the G4S Cash Business, who cannot be identified for security reasons, has supervised the delivery of millions in notes in recent months to 33 strategically chosen bank branches to coincide with the launch date. Across the UK, 38 carefully selected ATMs were also filled with the new notes by G4S.

As the new £20 notes are 15 percent smaller than the old notes, tens of thousands of cassettes in ATMs across the country will need to be replaced or reconfigured. The planning behind this, production planning, the cash centre operation and the cash in transit routes had been going on for more than a year.

“We also want to make sure that those people who want to see the new £20 note on February 20 will be able to withdraw it from selected banks and ATMs,” the Project Manager said.

“All the cotton notes will be systematically replaced. Come the 20th, we will be delivering polymer only.”

Within two weeks of launch in England, it’s expected that every bank branch supplied by G4S will stock new notes. Within about six to eight weeks, every ATM will have been converted to the new £20 cassettes. G4S and other providers will begin to stockpile old notes in Cash Centre vaults, ready to be sent to the Bank of England to be destroyed.

“The life of a note is extraordinary,” Mark Saunders, Director of G4S’s Cash Centre Operations, said.

“After we’ve machine sorted the cotton notes out, they’ll be parcelled, weighed and sealed - in cages in our vaults before being securely transported back to the Bank of England for verification and destruction. It’s an enormous operation the general public will barely notice, and that’s the way we want it.” 

Mark Saunders, Director of G4S's Cash Centre Operations, in front of a high speed note sorting machine.