Decimalisation - 1971
On Monday 15 February 1971, Britain went decimal. The old money, pounds, shillings and pence, was replaced by a new system with 100 pence in the pound and no shillings. It seems simple to us, but at the time people worried about it. Imagine the confusion though, if we were to go the other way around.
New Half Penny
One New Penny
Two New Pence
Five New Pence
Ten New Pence
Fifty New Pence
On 15 February 1971 people were already used to some of the new money. The Royal Mint introduced the 5p, 10p and 50p in the 1960s:
- 5p and 10p - in 1968 to replace the shilling and florin coins
- 50p - in 1969 to replace the 10 shilling note
The Bank of England issued the last 10 shilling note on 13 October 1969. On the same day the Royal Mint issued the first 50p coins. The Bank called in 10 shilling notes on 20 November 1970. This meant that they were no longer legal tender, but you could exchange them at a bank. 
For a while the old and the new currencies ran hand in hand. People paid in pounds, shillings and pence and got change in new pence. The original plan was to keep the old money in circulation for eighteen months. In the end, the old penny, halfpenny and threepenny bits were no longer legal tender after August 1971.
How did people cope with two money systems at the same time?
Sixpence was the bridge
On D-Day (Decimal Day), 15 February 1971, people already had the new 5p, 10p and 50p in their change. They also had the old penny, threepenny bit, sixpence, one shilling and two shilling coins. The halfpenny, half crown and ten shilling note was already withdrawn.
Some shops were ready to take decimal money, others were not and had prices in £sd. So how did shopkeepers and customers work it out?
The sixpence was the bridge between the old and the new currencies. It was the smallest unit of old pence that converted to new pence without fractions of less than half a new penny. Sixpence was 2½p, but threepence, for example, was 1¼p and there was no coin for ¼p.
To buy in a decimal shop, you divided your £sd coins into six penny (6d) units and rounded the price up to nearest sixpence. The shopkeeper gave you the right change in decimal coins.
To buy in an £sd shop with decimal money, you rounded up to units of 2½p and the shopkeeper gave you £sd change.
For example, to buy a ½lb pack of Wall's sausages costing 11p with £sd coins:
1. Convert 11p to units of 2½p. 11p = 2½p x 4, but we still need to pay another 1p. So we convert it to 5 units of 2½p.
2. Convert to £sd coins. 5 x 2½p = 6d x 5 = 30d. 30d is two shillings (2 x 12d) + 6d or 2s 6d.
3. Pay the shopkeeper 2s 6d. He translates it to 12½p. She gives you change in decimal. So she gives you 1½p (12½p minus 11p) in change.
To pay in a £sd shop with decimal coins it was the other way around. For example:
To buy ½lb Stork margarine costing 1s 3d.
1. Round up to the nearest 6d. 1s 3d rounded up to the nearest 6d is 1s 6d.
2. Convert the 6d units to 2½p as you only have decimal coins. 1s 6d = 5p (1s) + 2½p (6d) = 7½p.
3. Pay 7½p
4. The shop keeper treats this as 1s 6d and the price was 1s 3d. So, gives you 3d in change.
This transition period only lasted until 31 August 1971. Although for one retailer it was to last signifcantly longer.
Mr Louis Durrant was the owner of L.L. Durrant Ltd, 58, England Lane, Gorleston-on-Sea, Near Great Yarmoth. He had worked in the retail trade for 53 years using pounds, shillings and pence and saw no reason to change. After the decimal transistion period finished he rounded his prices to the nearest 6d, so customers could pay the exact amount in decimal. 
His shop displayed a sign saying "Please note: all our goods are priced for sterling." He kept up his protest at least until 1974. 
What about bank accounts and cheques?
The banks closed on Wednesday 10 February 1971 and did not open again until Monday 15 February. In this time they converted all bank accounts to decimal.
They used the Banking and Accouting table to do the conversion. It used approximation to do a fair conversion. Bank accounts had no halfpennies, although there was a decimal halfpenny in 1971.
Cheques were not £sd or decimal until the customer filled them in. So there was no need to issue new cheque books.
People had to write cheques dated before 15 February 1971 in £sd. On or after 15 February they had to write amounts in decimal. People still paid old bills in £sd with decimal cheques. They used the Banking and Accounting table to do the conversion.
Rising prices was the biggest controversy with decimal currency. People thought the shops used it as an excuse to put up prices. This may have been true, as many changed their prices when the new money came in. But inflation was high in the 1970s and prices would have risen anyway.
There was a remarkable evolution in design from the old money coins first minted in 1953 (see old money). Although they depict similar motifs, there is a much more contemporary feel to them.
"New Pence" and "New Penny" have now gone - to call anything from 1971 "new" is stretching it a bit!
Britain's first decimal coins
If you want a souvenir of the Britain's first decimal currency you can buy an original set of coins from 1971 for around £1 on eBay. See
 Promises to Pay, the first three hundred years of Bank of England Notes, by Derrick Byatt, published 1994, Spink. Page 186.
 'The old order changeth not at Mr Durrant's till' by Ronald Faux, published in The Times 19 August 1972, page 3, issue 58556
 'How pennies and pounds added up in the past' by Peggotty, published 4 September 2014 and accessed online from the Great Yarmouth Mercury,
Add your comments
"what to your savings in the bank at the time of decimal change?" Carol 12/10/2018
"Banks converted customers' accounts to decimal currency before they re-opened on Monday 15 February in 1971. They used a conversion table called the Banking and Accounting table to do the conversion. Best regards" Steven 12/10/2018
"15 shipping is what into days money please" Jane 11/04/2019