http://www.ofcom.org.uk/telecoms/ioi/numbers/numbers_administered/download

These files are all of the comma separated variable (csv) type, using " " as text delimiters.

The fields contained within each file are as follows:
sabc.txt 	Code, D/DE, Status, Use, Notes, Date
s1_code.txt 	SABC, D/DE, Status, Date, Operator, Number Length, Change, Notes
s5_code.txt 	SABC, D/DE, Status, Operator, Notes, Use, Change
s7_code.txt 	SABC, D/DE, Status, Date, Operator, Use, Notes, Change
s8_code.txt 	SABC, D/DE, Status, Tariff Notes, Date, Operator, Use, Notes, Change
s9_code.txt 	SABC, D/DE, Status, Tariff Notes, Date, Operator, Use, Notes, Change
s10_code.txt 	Code, Type, Status, Function, Operator, Sub-Allocatee, Trading Name, Name of Service, Description of Service, Use, Withdraw, Change

The order of the fields within each file will be maintained. Any changes will be indicated in the 'Change Record', below.

In addition a readme.txt file is included.  This is a plain text file that contains further information regarding UK Telephone Numbers, including a definition of the contents of each field.  It is also used to notify changes that have been made to the codelist.zip files.            
CHANGE RECORD

Issue
	
Date
	
Summary of Change
1
	
15/12/99
	
First Issue
2
	
22/12/99
	
In sabc_de.txt - the ‘notes’ field has been moved to right-hand end.

3
	
29/02/00
	
A new file 'sabc_def.txt' has been added.

4
	
16/05/00
	
A new file 'cps_code.txt' has been added.

5
	
26/02/01
	
s9_code.txt has a 'Tariff Notes' field added, and cps_code.txt and nppc.txt have been removed (cps and nppc codes can now be found here)
6
	
27/03/01
	
A new table has been created sabc.txt, and tables s1_code.txt and sns_code.txt have been deleted.
7
	
26/06/01
	
A new table - s5_code.txt - has been added.
8
	
24/07/01
	
2 fileds have been added to the file: sabc_def.txt i.e. 'Notes' - showing number length, and 'Use' showing what number range is used for.
9
	
21/01/02
	
A new field - 'tariff notes' has been added to file s8_code.txt - showing the tariff for Special Service (non-internet) ranges, up to 5p, and up to 10p respectively.
10
	
23/05/02
	
Four new fields have been added to the s10_code.txt file, after the 'Operator' field: 'Sub-Allocatee'; 'Trading Name'; 'Name of Service'; and 'Description of Service'. These fields specifically relate to allocations of Directory Enquiry codes - 118XXX.
11
	
01/06/02
	

File sabc_de.txt has been renamed s1_code.txt.
File sabc_def.txt has been renamed s8f_code.txt.
A new file s1f_code.txt has been added which lists Geographic Type A Conservation Areas at 1k number level.
12 	13/11/06 	The numbering files no longer have separate downloads for s1 Geographic & s8 Non-Geographic 1k allocations. These are now included in the s1 & s8 downloads.