a standard voltage for homes in the united states is 110 v
Mains electricity
Following voltage harmonisation , electricity supplies within the European Union are now nominally 230 V ± 10 % at 50 Hz . For a transition period ( 1995 -- 2008 ) , countries that had previously used 220 V changed to a narrower asymmetric tolerance range of 230 V + 6 % / − 10 % and those ( like the UK ) that had previously used 240 V changed to 230 V + 10 % / − 6 % . No change in voltage is required by either system as both 220 V and 240 V fall within the lower 230 V tolerance bands ( 230 V ± 10 % ) . Some areas of the UK still have 250 volts for legacy reasons , but these also fall within the 10 % tolerance band of 230 volts . In practice , this allows countries to continue to supply the same voltage ( 220 or 240 V ) , at least until existing supply transformers are replaced . Equipment ( with the exception of filament bulbs ) used in these countries is designed to accept any voltage within the specified range . In the United States and Canada , national standards specify that the nominal voltage at the source should be 120 V and allow a range of 114 V to 126 V ( RMS ) ( − 5 % to + 5 % ) . Historically 110 V , 115 V and 117 V have been used at different times and places in North America . Mains power is sometimes spoken of as 110 V ; however , 120 V is the nominal voltage . 
Following voltage harmonisation , electricity supplies within the European Union are now nominally 230 V ± 10 % at 50 Hz . For a transition period ( 1995 -- 2008 ) , countries that had previously used 220 V changed to a narrower asymmetric tolerance range of 230 V + 6 % / − 10 % and those ( like the UK ) that had previously used 240 V changed to 230 V + 10 % / − 6 % . No change in voltage is required by either system as both 220 V and 240 V fall within the lower 230 V tolerance bands ( 230 V ± 10 % ) . Some areas of the UK still have 250 volts for legacy reasons , but these also fall within the 10 % tolerance band of 230 volts . In practice , this allows countries to continue to supply the same voltage ( 220 or 240 V ) , at least until existing supply transformers are replaced . Equipment ( with the exception of filament bulbs ) used in these countries is designed to accept any voltage within the specified range . In the United States and Canada , national standards specify that the nominal voltage at the source should be 120 V and allow a range of 114 V to 126 V ( RMS ) ( − 5 % to + 5 % ) . Historically 110 V , 115 V and 117 V have been used at different times and places in North America . Mains power is sometimes spoken of as 110 V ; however , 120 V is the nominal voltage .
No. In the United States and also in Canada , national standards specify that the nominal voltage at the source should be 120 V and allow a range of 114 V to 126 V ( RMS ). Historically 110 V , 115 V and 117 V have been used at different times and places in North America .
In the United States and Canada , national standards specify that the nominal voltage at the source should be 120 V and allow a range of 114 V to 126 V ( RMS ) Historically 110 V , 115 V and 117 V have been used at different times and places in North America . Mains power is sometimes spoken of as 110 V ; however , 120 V is the nominal voltage .