Preheat the oven to 350°F (180°C). Line two baking sheets with parchment paper.
In a large bowl, beat together the butter, brown sugar, and granulated sugar until creamy.
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
In a separate bowl, combine the flour, baking soda, cinnamon, and salt. Gradually add to the wet mixture.
Stir in the oats and raisins until fully combined.
Drop spoonfuls of the dough onto the prepared baking sheets, spacing them about 2 inches apart.
Bake for 10-12 minutes or until the edges are golden brown.
Remove from the oven and let cool on the baking sheets for 5 minutes before transferring to a wire rack to cool completely.