While Japanese law does allow expats to remit salary outside the country, most employers and employees choose to avoid doing so on account of Japan’s stringent wire transfer laws (any transfer equivalent of US$10,000 is reported to the relevant regulators), foreign exchange rate fluctuations, and the high costs of living in Japan. Instead, some opt to open foreign denominated cash accounts at the international banks, although this too opens up the employee to foreign exchange rate losses.
Bank transfers in Japan are largely very simple, particularly with the international banks as they allow online wire transfers after the routing of the money (between your account in Japan and your account overseas) is applied for in writing at one of the bank branches in Japan. Once at your bank branch, ask the tellers for an overseas wire application. The form is usually no more than a page in length and asks for specifics about the destination account details, how much is being transferred, and the reasons for the transfer. The costs for wire transfers naturally vary from bank to bank, but generally speaking the costs for doing so range from 2,500 yen to 4,500 yen per transaction. Once the application is confirmed, the transfer should appear in your overseas bank account within a few days.
Foreigners tend to prefer working with the major international players for all of their retail banking needs, particularly since the staff can all speak English. Citibank is the most prominent international bank in Japan, and their many branches (http://www.citibank.co.jp/en/index.html) offer a variety of services, including online wire transfers once the initial application is complete. HSBC (http://www.hsbc.co.jp/1/2/home) is a more recent entrant into the market and also provides online wire transfers, albeit their online transfer offering is in Japanese only at this time. Perhaps the most commonly used online transfer service for foreigners in Japan is Lloyds TSB (https://www.golloyds.com/index.php?marker⟨=en) which offers reduced rate transfers from both a physical branch location and an online as well.