short telephone numbers for texting - how do they work?

[Pinotage]

I'm puzzled how the short numbers (i.e. without the network code) used to enter competitions on TV etc work? Presumably all mobile operators must agree on them.

[Mobius1]

Well, I doubt it's any different to any other mobile number. Whereas a given mobile company might own a six digit number plus a prefix code, all numbers must be agreed by all operators, else you'd end up calling or texting somebody else just because your operator has a proprietary number system.

So, I suppose you could look at it like ALL numbers being present on a system (within the UK) for all the operators. In the same way that you can have a personalised number plate and still be traced back to you, the short numbers can still be traced back to a given TV station competition etc.

[ppk001]

Is there a good deep web search for reverse UK phone searching? I know you can use Google but only searches surface web (as opposed to deep web). Pipl does this but only looks up Us & canadian numbers.