Postcodes - An Explanation

[st13phil]

Sometimes in the cesspool that is Twitter, the odd golden nugget surfaces and this is one of them: https://twitter.com/marcxsmith/status/1358810728619212807

To save scrolling through it, here it is condensed:

According to a Royal Mail survey, 92% of people can recall their home postcode (that's compared to 77% who can recall their debit card PIN), and 17% of people can still recite the postcode of the home where they lived 12 to 30 years ago. But why are UK postcodes so memorable? It's all thanks to cognitive psychology!​

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Postcodes were originally designed to speed up sorting following the mechanisation of the postal system at the end of the 1950s and they were first trialled in Norwich in 1959.​

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The Post Office asked psychologists at the MRC Applied Psychology Unit at Cambridge University to help them in devising a memorable system. The project was led by Reuben Conrad & included PhD student Alan Baddeley. Conrad and co. opted for a mixture of digits and letters, limiting the total to 6 or 7 digit/letter combinations. This was due to research discovering that short-term memory has a capacity of between 5 and 7 pieces of information. Number only codes had proved too difficult to remember and have a small number of permutations (10 per digit), while letters have 26 permutations per letter. Combining letters and digits give you a much greater range. Codes had to be short, memorable and sort to street level.​

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It was decided that each code would begin with the initial letters of the town name (the outward code), for example, NOR = Norwich. These have since been revised and include a number (e.g. NR1, LS4, etc). The outgoing code is the most memorable, so if there are errors in the second half of the code (the inward code), at least it would still get to the right area. The inward code consists of 1 digit and 2 letters, corresponding to the street - this gives you a very large number of possibilities (10x26x26). The number is placed in the middle because it stands out and can assist recall, acting as cue for the final 2 letters where errors are most likely to occur.​

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You can send a letter by using just the house number and the postcode, but Royal Mail don't like that.​

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Although originally designed to speed up sorting, postcodes have become a vital part of our everyday lives, from Sat Navs to ordering takeaway.​

 

[zipdip]

That is very interesting,that postal system works well,so we do have some clever people left in this country,they are right you can remember old post codes,I can remember one from 14 years ago SS7 3YS and after a little brain searching,I have come up with a place I lived 30 years ago SS11 8QT,but had to look that up just to make sure.

 

[Deleted member 65149]

My son has a postcode that’s for his house alone (being in the middle of 80acres of land in South Wales). Out of interest, a few years ago I sent a letter to him with just his postcode on and nothing else, not even his name. It arrived two days later.

 

[Deleted member 65149]

That is very interesting,that postal system works well,so we do have some clever people left in this country,they are right you can remember old post codes,I can remember one from 14 years ago SS7 3YS and after a little brain searching,I have come up with a place I lived 30 years ago SS11 8QT,but had to look that up just to make sure.

I can remember the postcode of the house I left 53 years ago (W7 3BE). But I can’t remember my current mobile phone number.

(Actually, I’m cheating a bit with that postcode, It was my parents’ house until they were both dead, a mere 35 years ago.)

 

[Dryce]

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Postcodes were originally designed to speed up sorting following the mechanisation of the postal system at the end of the 1950s and they were first trialled in Norwich in 1959.​

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There was some smart stuff going on in the 50s and 60s.

IBM came up with the basic product barcoding system we have today.​

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And we had the revision of the road signage system. Though I get the feeling that current authorities have lost sight of it a bit.​

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Then we have some failures - original NHS numbers were a bit of a regional mess (or several regional messes) that has since been revised.​

The first postcode I lived at got changed not long after I moved out. That caused hiccups when giving proof of identity on applications for some years after where we had to give a previous address as the background check would not accept the old address on entry - but if you entered the new address it wouldn't match with its database because internally it held the old address.

 

[Darrell]

Our place in Greece has even got a road name!!

 

[GP801]

Contrast that to our Italian postcode - 5 digits, no letters, which covers an area of around 20 square kilometres

 

[Peter103]

Our Spanish house has a road name a house number and a postcode that more or less covers the Costa Blanca' coast from Alicante for 50 miles south, and inland to Orihuela Town. But each houses post is collected by owner either from a PO box in nearest town, or we collect 150 MTRS from home in locked post box, parcels are delivered to your house by a postman on a yellow, "Correos" motorbike, mann`ana (Correos, Espana Post office).

 

[Darrell]

Our Spanish house has a road name a house number and a postcode that more or less covers the Costa Blanca' coast from Alicante for 50 miles south, and inland to Orihuela Town. But each houses post is collected by owner either from a PO box in nearest town, or we collect 150 MTRS from home in locked post box, parcels are delivered to your house by a postman on a yellow, "Correos" motorbike, mann`ana (Correos, Espana Post office).

We have a PO Box as well.

In Skiathos town there are road names and numbered houses but no Post Codes, once you’re outside of town then just forget it.

If people want to come to our house we just tell them that you do a right at the beer wholesaler on the ring road, go up the hill, past the taverna that’s on the right and we’re about 50 metres on the left. I’ll leave the car outside so you’ll know which house.
It usually works.

 

[Steeve]

You can send a letter by using just the house number and the postcode, but Royal Mail don't like that.​

Don't see why this is an issue, so much simpler and surely all that is needed.

It's not as if they check the rest of the information. I've had examples where someone has inaccurately entered my postcode, and even thought the letter clearly has a different street name it still ends up in my letter box, so their sorting system is clearly only using the postcode and house number/name.

 

[artyman]

I a bit like registrations I can remember all the registrations of my cars

 

[Bryan Allman]

In italy we use the 5 number postcode system which can cover quite an area. So to help, the main roads (each of which can be a couple of hundred Km long), also have distance posts every 1/10th of a km, so all you need do is give your relevant distance marker and your road name and Roberto is your uncle

 

[Deleted member 65149]

We have a PO Box as well.

In Skiathos town there are road names and numbered houses but no Post Codes, once you’re outside of town then just forget it.

If people want to come to our house we just tell them that you do a right at the beer wholesaler on the ring road, go up the hill, past the taverna that’s on the right and we’re about 50 metres on the left. I’ll leave the car outside so you’ll know which house.
It usually works.

Reminds me of when I rented a holiday home in Tenerife about 40 years ago. I was told to collect the keys from the pink house on the left when you enter the village. Not much use when you arrive at night and there’s no street lighting!

 

[Peter103]

We have a PO Box as well.

In Skiathos town there are road names and numbered houses but no Post Codes, once you’re outside of town then just forget it.

If people want to come to our house we just tell them that you do a right at the beer wholesaler on the ring road, go up the hill, past the taverna that’s on the right and we’re about 50 metres on the left. I’ll leave the car outside so you’ll know which house.
It usually works.

Love Greece and Greek islands, in 1977 rode through France, Belgium Germany, The then Yugoslavia, on through Greece, caught Ferry to Corfu stayed 4/5 weeks in villa of friend Spiro's,took 4 days to get there 1880miles not a lot of motorways back then.
Returned on ferry from igoumanitsa to Brindisi on foot of Italy straight up Italy to Aousta in Alps through tunnel into Lauseanne Switzerland on through France Calais, Dover home to South London, at that time I had a Honda 500cc twin lovely bike.only 3days to get home. Only downside got home in August to hear Elvis had died, if we maybe fly out this year, with your directions we'll pop round for a swift half.love it.,,

 

[Benzowner]

When we moved into my current house, 43 years ago, the post code was BS15 6DF it is now BS30 8DF. I can understand the first half, they just made the postal area smaller, but I always thought the second half was related to Ordnance Survey. With the building of new houses in the area, we also moved from Cadbury Heath to Warmley, a better area

 

[Petrol Pete]

The postal code system in the UK is a marvel, when years ago I first heard the 'house number plus postcode' will get the letter I started testing it out from time to time when I worked overseas. I would post an envelope with the house number and postcode and making sure 'United kingdom or Great Britain' was written in the local language . From memory I think almost all of them made it home.

It's only when you live or work outside of the UK do you realise how good our postcode system is. A few examples of my own experiences if I may .

Working in Morocco, bloke picks me up at airport (old MB E class W115) I have an address for the hotel something like ' 8KM Taroudant N10 sud' , basically 8 cliks outside the town of Taroudant on the N10 south, we were approaching from the South which didn't help much . Needless to say the driver spent a long time on his phone in the pitch dark trying to find the place (set well back from the road) . I got a hire car during the job and for the life of me all the months I was there I could not find where the 8 kilometres started in the town centre. The ( French) owners of the hotel told me try as they might to get it changed that was the address they had to use .

Working in Jamaica . I was regularly flying into Kingston which is not really a tourist start point in JA, the ranch owners son used to do the airport run for me (via numerous bars) and his ranch would provide me with the necessary invoice . One trip for whatever reason I had to get a hire car and suddenly realised that despite having been back numerous times every airport run had gone via anonymous roads/tracks/bars and businesses and I had no bloody idea how to get from the airport to my destination. It was all so vague, left at the light at the end of the airport spur road ,through downtown Kingston (been there ?) head West on the Mandela highway until you see the signs for Spanish Town but DO NOT enter Spanish Town then join highway 2000 . OR go over the hills through Rock Hall to Sligoville and drop into Riversdale .

None of which is recommended in the dark on your own fresh out of the airport. Back to the postcode story, I rented a sat nav along with the car. I couldn't find any address in the unit that was of use to me (remember I knew where I was going even if I did not know how to get there..eh ?) The bloke at the Avis desk asked me if there were any notable landmarks where I was working and I said no . He said have you eaten any take away food near the place you are workin at and I said yes KFC in the next town and a branch of Juici Patties just outside the factory, he said OK type that in an you are all good...he was correct.

Anyway enough of that. Our postcode system is brilliant.