For purchases made at www.sense.com:

While we hope that you’ll never need to, you may return your Sense Home Energy Monitor for any reason within 120 days of receipt for a full refund of your purchase price. To request a refund, please contact us for a Return Merchandise Authorization (RMA). In your request, kindly include your reason for returning your Sense monitor. The RMA must be included with your return shipment to us so that we can properly refund your purchase. Your returned monitor must be shipped within 14 days of the RMA. Purchases at other retailers are subject to those retailers' return policies.

For purchases made at Amazon:

If you purchased your Sense Home Energy Monitor through Amazon, you are able to submit a return to Amazon within 30 days of receipt for a refund. Please contact Amazon directly to submit your return.