How do I know if a phone number in the UK is using a VOIP service to re-direct to another country?

Question by James: How do I know if a phone number in the UK is using a VOIP service to re-direct to another country?
I am trying to find out if a person that wants to place a large order with my company is legit. Is there a way of looking up a UK phone number to determine if it is a land line, cell phone, or if it is a VOIP re-direct service?

Best answer:

Answer by Shanavas
From the number you can obviously make out if it is a landline or a mobile number. However, if your customer is using VoIP, it will be extremely difficult to track this. Even if you get hold of someone in the telecom company, they generally can’t reveal this due to privacy laws.

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