Preheat the oven to 350°F (175°C) and grease a 9x5-inch loaf pan.

In a bowl, whisk together the flour, baking powder, baking soda, and salt.

In a separate bowl, cream the butter and sugar together, then beat in the eggs and vanilla extract.

Alternate adding the dry ingredients and the buttermilk to the wet mixture, mixing just until combined.

Gently fold in the blueberries.

Pour the batter into the prepared loaf pan.

Bake for 50-55 minutes, until a toothpick inserted in the center comes out clean.

Cool in the pan for 10 minutes, then transfer to a cooling rack.