We have a heated mattress pad. All of the heat stays with you and the airspace under the blanket, and most of them work on a 12 hour timer. We can keep the thermostat colder at night because we have the heat where we need it.

I don’t remember the brand, but I bought it at Bed Bath and Beyond a year or two back. I don’t remember if it was about $100 before the 20% off or after, but it was pricey enough I made sure to get that coupon. Only wish I’d bought it sooner.