The new plastic £5 note is being launched in England and Wales on Tuesday, but most people may have to wait up to a week to get one.
The polymer note - which is much more durable than the old fiver - will initially only be available from a handful of banks and cash points.
ATMs in London, Manchester, Birmingham, Leeds, Hull and Cardiff will be among the first to stock them.
But only about 7% of cash machines dispense £5 notes in any case.
However, most bank branches are expected to have the notes within a week or so, suggesting those who want to obtain one may have to go into a bank and ask for one.
In Scotland, some plastic notes have been available on a limited basis since March 2015.
The Clydesdale Bank will stage a full roll-out of plastic notes later this month, followed by the Bank of Scotland and the Royal Bank of Scotland in October.
In Northern Ireland the first plastic notes were issued in October 1999 by the then Northern Bank - now known as Danske Bank.
Two million notes were put into circulation to mark the millennium.
The new fiver will depict Winston Churchill on the back.
The governor of the Bank of England, Mark Carney, said the new note would be cleaner, safer and stronger.
"The use of polymer means it can better withstand being repeatedly folded into wallets or scrunched up inside pockets, and can also survive a spin in the washing machine," he said.
However, the notes are not indestructible.
New security features - such as a transparent window - will make the note harder to counterfeit.
The polymer notes are expected to last an average of five years - compared to the current note's two years.
The old fiver will continue to be valid until 5 May 2017, by which time the Bank expects most of them will have been removed from circulation.
A total of 440 million new £5 notes have been printed.
A new polymer £10 note featuring Jane Austen is due to be released in a year's time, with a £20 note, featuring the artist Turner, to be launched by 2020.
The new notes will also be easier for blind or partially-sighted people to use.
"To help blind and vision impaired people distinguish between denominations, the notes retain tiered sizing and include bold numerals and similar colour palettes to the current notes," said Victoria Cleland, the Bank of England's chief cashier.
"In addition, polymer £10 and £20 notes will each have a tactile feature created by a series of raised dots, and the £5 note will be distinguishable by the absence of a feature."