The highest affiliate commission percentage for a forex broker can reach up to 50%. You can earn this commission by referring clients who deposit and trade with the broker. Some brokers offer tiered commissions based on the number of clients you refer. The commission can vary depending on the broker and the type of account your referred clients open. You can also earn additional bonuses if your referrals generate significant trading volume. Always check the affiliate program details for each broker to know their specific commission structure. Many forex brokers offer competitive commissions to attract affiliates.