McDonald's has set specific rules and restrictions for its 2025 customer survey at mcdvoice.com survey to ensure fair participation. Customers must be at least 18 years old and have a valid purchase receipt with a survey code. Each receipt is valid for one survey per visit, and employees or their immediate family members cannot participate. The survey must be completed within seven days of purchase, and rewards, such as discounts or free items, are non-transferable and cannot be exchanged for cash. Participation is limited to the United States, and McDonald's reserves the right to modify terms anytime.