There are many reasons why you may have regular payments to make overseas :
Often these payments go through a bank. Banks charge a premium for sending money overseas, while dedicated international money transfer companies offer a quicker service for less.
OFX and TorFX offer their clients recurring transfers. They are regulated as a bank, so your money is safe. Once set up with your account manager you have nothing to worry about. The payment is made automatically at the specified dates using the best rates available.