Preheat the oven to 200 C. Grease the muffin tin or line it with paper liners.
Mix the flour, sugar, salt and baking powder together in a bowl. Mix the oil, eggs and milk with a whisk and add to the dry ingredients. Mix everything well. Finally fold in the blueberries.
Spread the batter over the 12 muffin baking tins and bake on the middle rack for 20-25 minutes.