Yes, YouTube TV promo codes are typically case-sensitive, so you must enter them exactly as provided. Entering a code with the wrong capitalization or extra spaces can trigger an error message like “This code isn’t valid.” This is a common pitfall, especially when manually typing codes from third-party sites or emails. YouTube TV’s checkout process expects the code to match exactly, including any uppercase or lowercase letters. Pro tip: Always use copy-paste when entering promo codes to avoid case or spacing mistakes, and double-check for any hidden spaces before or after the code.