If your device is connected on the app, you can simply click "Replace My Filter" > "Order Filter" and select "One Time Purchase" or "Sign up / Manage Filter Subscription" which will take you straight to the correct filter on blueair.com. ​

If your device is not connected on the app, you can visit our filter page here https://www.blueair.com/us/air-purifier-filters and select Classic Pro as the family and your model as the series.