Sort the berries: Pick through your blueberries to remove any stems, leaves, or overripe berries.
Don’t wash (unless you must): If you're freezing for smoothies or baking, skip washing until you’re ready to use. If you prefer to wash now, be sure to dry them thoroughly.
Line a tray for flash freezing: Spread the berries in a single layer on a parchment-lined baking sheet, keeping them from touching.
Freeze until solid: Place the tray in the freezer for about 1–2 hours or until the berries are completely frozen.
Transfer to containers: Move the frozen berries to labeled freezer bags or jars. Remove as much air as possible.
Store for later: Keep frozen blueberries in the freezer for up to 12 months. Use them straight from the freezer in your favorite recipes.