Is USDT transfer free?

Excuse me, I'm a bit confused about USDT transfers. Could you clarify whether the transfer of USDT is free? I've heard some rumors that it's cost-free, but I'd like to get a confirmation from a professional like you. Is there any fee involved when transferring USDT between wallets or exchanges? I'm trying to plan my crypto transactions more efficiently, so this information is quite crucial for me. Could you please elaborate on this matter?