When it comes to milk tea, how long it lasts really depends on how it was made in the first place. If your milk tea was made with fresh milk, then it will only last for a day or two in the fridge before starting to spoil. However, if your milk tea was made with condensed milk or evaporated milk, then it can last up to a week in the fridge without spoiling. Ultimately, it is best to consume your milk tea within a few days of making it to ensure that it is at its freshest and best tasting.