Premium-rate telephone numbers are telephone numbers for telephone calls during which certain services are provided, and for which prices higher than normally are charged.
Telephone companies typically offer blocking services to allow telephone customers to prevent access to these number ranges from their telephones.
In some jurisdictions, telephone companies are required by law to offer such blocking.
Adult chat lines (phone sex) and tech support are a very common use of premium-rate numbers.
Other services include directory enquiries, weather forecasts, competitions and voting (especially relating to television shows).
Diplomatic services, such as the US embassy in London or the UK Embassy in Washington, have also charged premium rates for calls from the general public.
In many European countries, for example France, Germany and the United Kingdom, it is common for organisations to operate customer service lines on premium-rate numbers using prefixes that fall outside the scope of the country's premium-rate number regulations.
Therefore, in contrast to North America where customer service numbers are typically free of charge to the caller, consumers in Europe often pay a premium above the cost of a normal telephone call.
Computer criminals have used premium-rate numbers to defraud unsuspecting Internet users.
One scheme involved inducing users to download a program known as a dialer that surreptitiously dialed a premium-rate number, accumulating charges on the user's phone bill without their knowledge.
Another now-uncommon premium-rate scam involves television programming that induces young children to dial the number, banking on the notion that they will be unaware of the charges that will be incurred.
One variant, targeted at children too young to dial a number, enticed children to hold the phone up to the television set while the DTMF tones of the number were played.