Thread: Общие вопросы (General Questions)/All you need to know about UK Address Elements

All you need to know about UK Address Elements


Your address is made up of many parts, sub-building number, dependent thoroughfare, town and postcode to name a few. Every address in the UK contains some of the elements listed below, but not all of them. The only compulsory elements are the town and postcode. When you are implementing an address management strategy you will need to consider how you handle each of these elements.

Below is a list of each element present in PAF and the associated element code for use in your configuration files, accompanied by an example.

Organisation – O11

These are the names of organisations that are listed on PAF.

Example: QAS Ltd

Department – O21

These are the departments within organisations that have their own listing on PAF.

Example: Department of Obstetrics & Gynaecology

Whole PO Box – B11

A number of companies have a PO Box for one of two reasons. The first is because they wish their address to be withheld from the public in order to retain a degree of anonymity. However the organisation name is occasionally included and therefore it is only the address that is anonymous. A second reason for having a PO Box is to have the post pre-sorted before being delivered by Royal Mail. This typically happens in organisations which have large volumes of mail delivered each day to particular departments.

Example: PO Box 12

The PO Box can be split into two separate elements if required:

PO Box (Name): PO Box (B111)

PO Box (Number): 12 (B112)

Sub-building name – P22

Where a premise is split into a number of flats, apartments or business units, PAF lists these against the building name or number as separate delivery points. Note that flat details are only included if separate delivery points (letter boxes) exist.

Example: Flat 2

Whole sub-building number – P21

A sub-building number is included when a premise is split into a number of flats, apartments or business units, labelled with a number rather than a string of letters (e.g. the word “flat”). These are often found in towns in Scotland, with tenement addresses.

Example: 1G

The sub-building number can be split into two separate elements if required:

Sub-building number (Primary): 1 (P211)

Sub-building number (Additional): G (P212)

Building name – P12

A building name may be the name of a house or the name of commercial premises.

Example: Ocean Towers

Whole building number – P11

This is the number that identifies the premises on a thoroughfare or dependent thoroughfare. Most often, this is just a number, however it can contain both a number and letter (e.g. if an extra property is inserted at a later date between two consecutively numbered properties, or in purpose-built blocks of flats)

Example: 27a

The whole building number can be split into two separate elements if required:

Building number (Primary): 27 (P111)

Building number (Additional): a (P112)

Whole Dependent thoroughfare – S21

When a thoroughfare name exists more than once within a town, it is necessary to store additional information to uniquely identify each one. For some small roads it is possible to make it dependent on an adjoining road. For example there are two addresses containing ”1 Gorse View” in Saxmundham:

1 Gorse View

1 Gorse View


School Road





IP17 3BW


IP17 1TS

In the second address, Gorse View is dependent on School Road to identify it in the absence of locality or postcode information, therefore for this address Gorse View is a dependent thoroughfare. (In the first address Gorse View is a thoroughfare)

Example: Gorse View

The dependent thoroughfare can be split into two separate elements if required:

Dependent thoroughfare (Name): Gorse (S211)

Dependent thoroughfare (Descriptor): View (S212)

Whole thoroughfare – S11

This is the street that contains the delivery point (unless there is a dependent thoroughfare included in the address).

Example: High Street

The dependent thoroughfare can be split into two separate elements if required:

Dependent thoroughfare (Name): High (S111)

Dependent thoroughfare (Descriptor): Street (S112)

Double dependent locality – L41

It is possible that a thoroughfare exists twice within the same dependent locality. In this case the thoroughfare needs to be identified by a further locality, the double dependent locality. This is typically a village or hamlet. An example of this is Miry Lane in Huddersfield:

2 Miry Lane

2 Miry Lane









The correct Miry Lane can be identified by using the double dependent locality.

Example: Netherthong

Dependent locality – L31

As mentioned above, when a thoroughfare exists more than once in a town it needs to be uniquely identified. It is not always possible to make it dependent on another thoroughfare, so instead it can be made dependent on a locality. For example if we want to find 1 Back Lane in Huddersfield we see that there are three:

1 Back Lane

1 Back Lane

1 Back Lane


Clayton West








The correct Back Lane can be identified by the dependent locality.

Example: Holmfirth

Submitted PNR locality – L32

A postally non-required (PNR) locality is one that is commonly used to identify part of a town but is not officially required in addresses; it is not on the Royal Mail’s PAF. Experian QAS supplement the GBR data in its products with a separate list of PNR localities, also from the Royal Mail.

The Royal Mail list PNR localities to postal sector boundaries (e.g. SW4 0 for SW4 0QL). One of the problems associated with this is that a locality can appear in more than one postal sector and a postal sector can contain more than locality:

E9 5


E9 5

Hackney Wick

E9 5

South Hackney

E9 6


QAS products return PNR localities only if they are used in the search expression. The products will not suggest a PNR locality if the search expression does not contain one because there will probably be more than one ‘correct’ possibility.

Example: Clapham

Town – L21

This is the postal town for the address. It is worth noting that this may not always be the same as the administrative town boundary.

Example: Littlehampton

County – L11

This is the former postal county relating to an address.

Example: West Sussex

There are 4 different types of county, each with different boundaries.

  • Administrative
  • Geographical
  • Ceremonial
  • Former postal county

Due to many changes in the counties and their boundaries, Royal Mail decided to remove counties from its PAF file in December 2000. QAS continue to include counties in the data, counties now known as former postal counties. The counties are no longer updated by the Royal Mail, but QAS use the geographical boundaries to assign former postal counties to any new addresses that are added.

Dropping the use of counties in Experian QAS products would not suit the majority of customers who have counties already configured. Some customer databases have a requirement for a county field, and if Experian QAS products did not return this field it would mean blank spaces would be left in the data. Some end users of customer software also have preference for counties and would like the county included in the address. Therefore Experian QAS products will still return counties as part of the address field if required to do so.

A second reason to continue to return counties is that they allow our customers to continue searching on county information, and help QAS Batch when matching against a legacy database that includes a county field. Consider the address “34 High Street, Newport”. Without the county information is impossible to know whether this is Newport in Shropshire, the Isle of Wight, or Wales and thus impossible for Batch to add the correct postcode.

If there is a requirement for the counties other than former postal counties (e.g. administrative counties that are updated as boundaries alter) they can be added as a DataPlus set by using QAS Batch.

Whole Postcode – C11

On average a postcode relates to 15 premises, but it can vary from 1 to 100 premises.

Example: SW4 0QL

Although it is becoming less common, a postcode may cover more than one thoroughfare or dependent thoroughfare. This means that the combination of both premises number and postcode may not be enough to uniquely identify a delivery point. An example of this is the number 7 with the postcode DT10 1NA that can have the following addresses:

7 Hinton St. Mary

7 White Horse Lane

7 Castlemans Cottages


Hinton St. Mary

Hinton St. Mary






DT10 1NA

DT10 1NA

DT10 1NA

If the premise is required to be uniquely identified, then the Delivery Point Suffix should be used.

There are six valid postcode formats:



M2 5BQ



M34 3AB






DN16 9AA







The last two characters of the incode cannot contain the letters:


The postcode can be split into different postcode sections. The table below illustrates how many of each postcode section there are in the UK:

Postcode section

Section title

How many in the UK?






Approx. 2 900

SW4 0


Approx. 9 730

SW4 0Q

Half sector

Approx. 130 000



Approx. 1 750 000

The postcode can be split into two separate elements if required:

Postcode (Outcode): SW4 (C111)

Postcode (Incode): 0QL (C112)

Country – X11

This is the country related to the PAF address. Note that the countries of the United Kingdom are not separated.

Example: United Kingdom

Three character ISO country code – X12

This is the two letter International Organization for Standardization country code (ISO 3166-1-alpha-3) for an address.

Example: GBR

Two character ISO country code – X13

This is the two letter International Organization for Standardization country code (ISO 3166-1-alpha-2) for an address.

Example: GB

Delivery Point Suffix – A11

On average, a postcode contains 15 delivery points, each of which is uniquely identified by the delivery point suffix. This is a two-character code (a numeric character followed by a letter). It never appears in addresses. A combination of the DPS and the postcode is a unique reference for that particular delivery point.

Example: 1A