In cold weather, an ICE vehicle typically loses about 10% to 15% of its fuel economy, and in very cold conditions the drop can be a bit higher. That means a car that usually gets 30 mpg might fall to roughly 25–27 mpg in winter.

What affects the drop

  • Short trips cause the biggest hit because the engine spends more time warming up.
  • Thick oil, winter fuel blends, and extra idling also reduce efficiency.
  • Snow, slush, and cold tires add rolling resistance.

Typical winter impact

Condition| Typical loss
---|---
Mild cold| about 5% to 10%
Freezing weather| about 10% to 15%
Severe cold, short trips, lots of idling| 15%+

Easy example

If your SUV normally gets 24 mpg, a 15% winter loss brings it down to about 20.4 mpg. Over a full tank, that can mean noticeably fewer miles between fill- ups.

How to reduce it

  • Keep tires properly inflated.
  • Avoid long warm-up idling.
  • Combine trips so the engine stays warm.
  • Use the recommended oil grade for winter.

For your wording, if you meant “ICE” as in internal combustion engine, the answer above applies.