You do not need to have a US address to file a tax return with any of the TurboTax editions, including the Free edition.
What you need if you upgrade your online account above the Free edition is a US credit card with a US billing address to pay any TurboTax account fees.
Additionally, if you have a tax refund, the refund can only be direct deposited into a US bank account with a bank located in the US. Otherwise, the refund check can only be mailed to the address on the tax return.
