Premium Bonds take a quantum leap as new random number generator, ERNIE 5, picks two new jackpot winners for March

ERNIE 5 quantum chip
ERNIE has regenerated for the first time in 15 years, and is using quantum technology to generate random numbers. NS&I has also become one of the UK's first financial organisations to create an Alexa Skill, giving Premium Bonds customers another way to check their prizes.
  • A new ERNIE, using quantum technology, generates its first random numbers, creating two new millionaires in Somerset and Buckinghamshire
  • ERNIE 5 helps draw over three million prizes worth £92 million for March’s Premium Bonds draw
  • When ERNIE met Alexa: Customers can check for their prizes using Alexa for the first time

Since Premium Bonds were launched in 1956, a very special machine has won the affections of the British public, one representing the hopes and dreams of 21 million Premium Bonds holders across the UK and overseas. ERNIE, the Premium Bonds random number generator, is responsible for drawing over three million prizes each month, worth more than £90 million.

The popularity of Premium Bonds has soared so much so that over 79 billion Bonds are now eligible to win any of the three million prizes each month. After 15 years of loyal service, ERNIE 4 has been decommissioned and replaced with a faster machine to cope with the increasing volume of numbers that have to be produced every month.

ERNIE 4 will spend retirement in the leafy surroundings of Bletchley Park, after being handed to the National Museum of Computing. The concept for the very first ERNIE was created here, by Tommy Flowers, builder of the code-breaking Colossus during World War Two.

The Power of Premium Bonds: ERNIE 5 taking a quantum leap

All previous ERNIEs have used thermal noise to produce random numbers, however ERNIE 5 is powered by quantum technology, the ability to produce random numbers through light.

This new technology, developed by ID Quantique (IDQ), has allowed ERNIE to produce enough random numbers for March’s prize draw in just 12 minutes, far superior to the 9 hours that ERNIE 4 took towards the end of its random number generating-career.

Checking prizes has also evolved

Customers can now check prizes through the official NS&I Premium Bonds prize checker Alexa skill as well as using the prize checker on and downloading the official Premium Bonds prize checker app from the Apple App store or Google Play. This is one of the first retail banking voice applications to the UK market.

ERNIE through the generations

Year 1957-1973 1973-1988 1988-2004 2004-2019
Number of prizes paid out per draw (at end of the machine's life - rounded) 90,000 192,000 1 million 3 million
Value of prizes paid out per draw (at end of machine's life - rounded) £3.7 million £11.5 million £57 million £92 million
Investment in Premium Bonds (at year of introduction) £49 million £969 million £2.2 billion £25 billion
Time taken to run draw (at end of machine's life) 10 days (1973) 5.5 hours (1988) 5.5 hours (2004) 9 hours (2019)
Processing speed (Bond numbers per hour) 2,000 65,000 330,000 1 million


Ian Ackerley NS&I Chief Executive, said:

“Premium Bonds are as popular as ever before and ERNIE has been an integral part of that journey, changing the lives of millions of our customers since 1957.

“But ERNIE and Premium Bonds are also moving with the times; ERNIE, using quantum technology, will now be able to generate the millions of numbers required at a much faster pace, continuing to give customers a chance to have some fun while having a secure place for their savings.

“Meanwhile customers can use digital channels to check and manage Premium Bonds – from asking Alexa to check prizes to getting prizes paid directly into their bank account – saving and winning is easier, faster, and more accessible than ever before”

Ask Alexa to check Premium Bonds prizes

ERNIE 5’s March millionaires

The first eligible Bond numbers to be generated by ERNIE, winning the two £1 million jackpot prizes, belong to a man from Somerset and a woman from Buckinghamshire.

The Somerset winner, who holds the maximum amount of £50,000 in Premium Bonds, has held his winning Bonds since September 2015 (winning Bond number: 256SE420168).

The second millionaire for March, a woman from Buckinghamshire holds £33,116 in Premium Bonds, and purchased the winning Bond in May 2016 (Winning Bond number: 272TH828201).



Premium Bonds are one of the most popular savings products, offering tax free prizes which can be paid directly into customers’ bank accounts. The minimum investment is now just £25 and can be bought as a gift for children under 16 by parents and grandparents.

Since the launch of Premium Bonds in 1956 ERNIE has created 406 millionaires and generated the numbers for over 432 million prizes totalling £19.2 billion. Today, ERNIE has drawn over three million prizes worth more than £92 million.

March 2019 prize draw breakdown

In the March 2019 draw, a total of 3,252,781 prizes worth £92,975,275 will be paid out. There were 79,693,094,848 eligible Bonds for the draw.

Value of prize Number of prizes
£1,000,000 2
£100,000 5
£50,000 11
£25,000 22
£10,000 52
£5,000 106
£1,000 1,859
£500 5,577
£100 25,491
£50 25,491
£25 3,194,165
Total value of prizes

Total number of prizes

Notes to editors

  1. All Premium Bonds prizes are free of UK Income Tax and Capital Gains Tax.
  2. NS&I is one of the largest savings organisations in the UK, offering a range of savings and investments to 25 million customers. All products offer 100% capital security, because NS&I is backed by HM Treasury.
  3. ID Quantique (IDQ) – builders of ERNIE 5 - is a global company founded in 2001 and headquartered in Switzerland, with engineering and research labs located around the world. IDQ has established itself as a leader in the fields of quantum-safe cryptography, scientific instrumentation and random number generation. IDQ is dedicated to remaining the global leader in Quantum Sensing & Quantum Cryptography solutions. Its products are used by governments, enterprises and academic customers in more than 60 countries and on every continent.
  4. The annual Premium Bonds prize fund rate is currently 1.40% and the odds of each individual Bond number winning any prize are currently 24,500 to 1.
  5. Pictures of the power behind ERNIE 5, the previous ERNIEs and Premium Bonds, including the Premium Bonds app are available in high-resolution jpeg format from the NS&I media team.

7. Some prizes that ERNIE 5 has generated numbers for may also become unclaimed after 18 months, as a result of Premium Bonds holders changing their addresses and not keeping other details up to date with NS&I. A total of 1.5 million prizes remain unclaimed, totalling over £60 million.

  1. Customers can buy Premium Bonds online at and over the phone by calling 08085 007 007. This is a freephone number and calls to it from the UK are free from both landlines and mobiles. Calls may be recorded. Customers can also buy by post. Existing customers can also buy by bank transfer and standing order and currently each investment must be at least £25 for bank transfers and standing orders.