Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper if desired.
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
Beat in the eggs, one at a time, followed by the vanilla extract until well combined.
In another bowl, whisk together the rolled oats, all-purpose flour, baking soda, cinnamon, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Gently fold in the raisins using a rubber spatula, ensuring they are evenly distributed throughout the dough.
Drop rounded tablespoons of the dough onto the prepared baking sheets, leaving about 2 inches between each cookie.
Bake in the preheated oven for 10 to 12 minutes, or until the edges are golden brown and the centers look set.
Remove the cookies from the oven and let them cool on the baking sheets for 5 minutes before transferring them to a wire cooling rack to cool completely.