The domestic voltage used in Canadian homes is between 110 and 120 volts, notes Adaptelec, a website featuring advice from international electrical specialists. "Type B" North American NEMA 5-15 standard outlets are used and have one grounded plug and two narrow rectangular holes. The outlets are not polarized, meaning one prong isn't narrower than the other.
Since the domestic voltage in Canada may be different from that of their home countries, travelers particularly need to ensure that any electric devices they bring to Canada have plug adapters and a transformer, if necessary. For example, Japan uses 100 volts for appliances, so a special transformer is needed to successfully use Japanese devices in Canada. When devices are 220 volts, both a transformer and a plug adapter are required. Using a plug adapter in Canada alone won't suffice if the voltage differs, warns Adaptelec.