| Title | Test
                    Find
                    
                    UK Phone Number in 5-3-3 Format | 
            
                | Expression | ^[\d]{5}[-\s]{1}[\d]{3}[-\s]{1}[\d]{3}$ | 
            
                | Description | Allows dashes or spaces to separate. | 
            
                | Matches | 08000 333 333  |  08700-333-333  |  08440 333-333 | 
            
                | Non-Matches | 08000333333  |  08000=333=333  |  08000  333  333 | 
            
                | Author | Rating:
                        
Not yet rated.
                    Matthew Harris | 
            
                | Source |  | 
            
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	                Title: Incomplete and incorrect.
	                Name: g1smd
	                Date: 10/28/2012 6:31:34 PM
	                Comment: 
The ^[\d]{5}[-\s]{1}[\d]{3}[-\s]{1}[\d]{3}$ pattern is very inefficient. The [\d]{5} should be just \d{5} here. The [-\s]{1} should be just [\s-] here. The [\d]{3} should be just \d{3} here. However, this pattern matches only 4+6 format numbers. It fails to match valid UK 2+8, 3+7, 4+5, 5+5 and 5+4 format numbers.  Use the pattern in http://www.regexlib.com/REDetails.aspx?regexp_id=3606 to validate the format, the pattern in http://www.regexlib.com/REDetails.aspx?regexp_id=3607 to extract the NSN, and the pattern in either http://www.regexlib.com/REDetails.aspx?regexp_id=3608 or http://www.regexlib.com/REDetails.aspx?regexp_id=3609 to validate the NSN. 
                
                
            
                
	                Title: 5-3-3 is not a valid UK format.
	                Name: Steve.
	                Date: 11/4/2011 5:34:22 AM
	                Comment: 
Most UK telephone numbers can have either 9 or 10 digits after the 0 trunk prefix. The initial 0 is omitted when calling from abroad.
01 and 02 area codes should have parentheses around them if the local number part does not begin with a 0 or 1. 01 and 02 area codes do not have parentheses around them if the local number part begins with a 0 or 1. These are National Dialling Only ranges.
All other area codes do not have parentheses around them as the area code is required for all calls. Number formats are expressed as:
2+8 to represent (02x) xxxx xxxx [in 5 areas] or 05x xxxx xxxx or 070 xxxx xxxx or 076 xxxx xxxx.
3+7 to represent (011x) xxx xxxx [in 6 areas] or (01x1) xxx xxxx [in 6 areas] or 03xx xxx xxxx or 08xx xxx xxxx or 0800 xxx xxxx or 09xx xxx xxxx.
3+6 to represent 0500 xxxxxx or 0800 xxxxxx.
4+6 to represent (01xxx) xxxxxx [in 580 areas] or 07xxx xxxxxx.
4+5 to represent (01xxx) xxxxx [in 41 areas].
5+5 to represent (01xx xx) xxxxx [in 12 areas].
5+4 to represent (01xx xx) xxxx [in 1 area].
Valid formats include:
(011x) - 3+7. 
(01x1) - 3+7. 
(01xxx) - 4+6 or 4+5. 
(01xx xx) - 5+5 or 5+4. 
(02x) - 2+8. 
03xx - 3+7. 
05x - 2+8. 
0500 - 3+6. 
07xxx - 4+6. 
070 - 2+8. 
076 - 2+8.
08xx - 3+7. 
0800 - 3+7 or 3+6. 
09xx - 3+7. 
There are a small number of exceptions such as 0800 1111 and 0845 4647. 
The UK system is quite complex!