How do UK postal codes work?


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My mate thinks a postal code is for a small area of a street, whereas I believe a postal code links one side of a street and the other side has a different postal code as that's how it's been at the 11 places I've lived.

Which is more correct?

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First two letters are sorting office, next number is an area in the catchment area that the delivery office delivers to and also which delivery office to send the post to, the next number is the area of town around the delivery office and the last 2 letters signify a group of house numbers up to 80 i think.

tecnically, its both.

our postcode encompases 1 side of the road and about 1/2 of it lengthwise.

i think theres 5 postcodes used on my road. and thers only 150 houses.

That's really strange. In all the places I've lived, some really long roads included, there are only and always two postal codes used.

We have two postcodes, one for each side of the street (one for the odd numbers on our side, one for the evens on the other). The only difference is the letter at the end though. It probably depends on the layout of the street (i.e. if it's a cul-de-sac, non-through road, etc) and the number of houses.

Postcodes can, and do now at mail centres, resolve down to individual residences, even if you share the same postcode.

There's an extra 2 digit alpha-numeric that's hidden from "end users", so a postcode for buckingham palace would not be SW1 1AA but actually SW1 1AA 1A.

Post codes are limited to a certain number of houses I forget how many but 80 seems about right.

Generally:

Post codes are one street unless the road only has a couple of houses on.

Post codes in cul de sacs or very small quite roads will be any house

Most roads its different for each side (presumably so that when sorted by code and then house number the postie doesn't have to keep crossing the road after each house?)

+Mike Chipshop suggesting the houses are random is very bizarre (id actually suggest he's mistaken) many different ones may exist on a road if houses have been built been houses later on. Especially when blocks of flats have been put in mid way down the road as large flats may have individual post codes. But I find it doubtful only 8 out of 130 houses have the same - why/how would you even know the postcodes to everyone on your street?

There is more logic to them than you'd think, whereI used to live there was about 10 parallel roads built at the same time and all have very similar post codes - I know several people who live round the area and the only difference is the last character. Try typing in your post code into google and adjusting the last letter to see the next block. Obviously the system allows for inserting additionals roads so random ones are likely to not exist.

for example my current post code ends in N and is less than 20 years old... changing the last character for N-Z all the postcodes which exist are newer streets built after mine and all within half a mile.

why/how would you even know the postcodes to everyone on your street?

Ordering Pizza to my house online :p (I'm hungry and do it a lot from various different companies (Gogo, Hut, Dominos, Papa Johns etc).

Also when using Parcel Force worldwide for a pickup.

Ordering Pizza to my house online :p (I'm hungry and do it a lot from various different companies (Gogo, Hut, Dominos, Papa Johns etc).

Also when using Parcel Force worldwide for a pickup.

How would ordering pizza tell your all the post codes on your street? :s maybe im being dim but im confused - surely at best it would list all the houses with the same post code once you submit your post code.

Usually they ask for house number and post code - as that is all they need to find your house. I'm still baffled how you are 100% sure what your neighbours post codes is or even more so those who live down the street.

Well obviously i haven't been to all my neighbours and asked them (a few i know anyway and know they have different postcodes) but i have just double checked and there are 5 houses on my street with my postcode, i'd estimate between 130 -140 houses on the street.

If i go to order a pick up or pizza delivery via the internet, first i have to type in my postcode, next it gives me list of addresses that correspond to that postcode. On every site that it does this it always lists 5.

I live in the East end of London and the area was heavily bombed in the blitz... i'm thinking maybe my road was a different road or some major shuffle went on at some point.

(but to throw a spanner in the works further, my road wouldn't even have been in London during the war it would still have been part of Essex)

In UK to reach a particular house/place one must have only 2 things

1. House Number

2. Full Post code

Post code must have 2 parts

GU12 5BZ

In the first part GU12, the GU indicates the presence of major city here being Guildford and 12 indicates the zone. Which can be a nearby smaller town and not Guildford itself.

The second part 5BZ is simply the exact part of the street where the house is located in the GU zone.

So lets say for eg.

Name, Surname

150

GU12 5BZ

This data is completely sufficient for your mail to be delivered to you.

When I worked in Royal Mail, I came to know about these little bits as a part of the training :)

In the UK it works like that? My post code in spain covers the entire town (around 50k people). Here I think there is one code per post office.

Yeah, same in Australia. 3000 - 3999 is for areas inside of Victoria (a state), and then they just divide it all up and give each section a post code. The UK way seems incredibly complicated. :\

5 houses for a single postcode is perfectly reasonable - but you said every house was different and only 8 on the street were the same. If you meant at most 8 houses have the same that's pretty common.

Anyway to expand on sanke1 comments, after the first two letters corresponding to a major town in the example given GW, usually: GW1 would be the city centre of Guildford, with the next numbers creating a ring around the centre (eg. 2 is to the east, 3 is to the south etc. depending on the density this could be just 2 areas or 8 or more, and I believe it goes clock wise around the city not sure if there is a common start point). Then by that time the city itself is usually covered as well a satellite towns that merge with the city and the next "ring" will cover smaller towns. I'm --12 but 25 miles away from the city (and even in a different county!) to that referenced in the first two letters (it's my closest city still but that does not necessarily mean it has to be - its more a case of how post is delivered I believe, which is all post goes to a major city sorting office (GW), then to a local office (GW12), before getting delivered, there is no doubt sub sections to certain areas)

Yeah, same in Australia. 3000 - 3999 is for areas inside of Victoria (a state), and then they just divide it all up and give each section a post code. The UK way seems incredibly complicated. :\

Explain? I can't see how it's complicated - you get a post code area (the first two characters - e.g 'WD' is for Watford, 'BS' is for Bristol, and so on), then the remaining characters drill down into a district in the area, then a smaller area within that, and finally a street/section of dwellings/single dwelling depending on how the individual postcode is divided up.

Yeah our post codes are easy to understand. At least we use letters at the start to indicate which city area or county we are in unlike a lot of other places that just use numbers like the aussies and americans which just look like random numbers that tell us nothing without looking it up.

Yeah our post codes are easy to understand. At least we use letters at the start to indicate which city area or county we are in unlike a lot of other places that just use numbers like the aussies and americans which just look like random numbers that tell us nothing without looking it up.

So don't you guys include addresses when writing letters? Just a Post code? Addresses seem to help explain exactly where someone is. :s

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