This is one of our favorite first-time sign-up offers. Sign up for Second Nature and get a free air filter replacement for your home. First shipments are totally free for new customers — just select which size air filter you have at home and check out.

Note that Second Nature subscriptions require a valid credit/debit card at sign-up. The card will not be charged for the first shipment, except for a temporary $1 authorization to validate the card. You can cancel your subscription at any time.

get a free air filter from second nature

What is Second Nature?

Second Nature is a subscription service for home air filters. Choose the sizes and type of filters for your home, then select how often you want them delivered. They ship directly to your door on the date they need to be replaced.

When they arrive, all you have to do is pop them in and discard the old ones, Plus, the filters are high quality and often at a lower price than your local hardware store.

Here’s how to get the deal:

  1. Head to and click the green “Free? Yes Please” button.
  2. Enter your email and click “Unlock Now.”
  3. Select the number of air filters you’d like in your shipment; then click “Next Step.”
  4. Select the size of filter you need. Not sure which size you need? Click “Find My Filter Sizes” to get more information.
  5. Choose from their three different quality levels, starting at $12 after your first free month.
  6. Select how often you’d like to receive new filters.
  7. Enter your shipping and billing information and place your free order.

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