Both US-based brokers offer free ETF trading with 0% commissions and have low non-trading fees including no inactivity fees and deposit fees. However, if you are looking to trade stocks, then Fidelity is the most cost-effective option. Where Fidelity offers free US stock trading with 0% commission and access to international stock markets, Vanguard charges $7 commission for the first 25 traders per 12 months and $20 thereafter. Vanguard’s trading fees are tiered and vary depending on your account balance.