Outdoor extension cords die after 2–5 years. Plan accordingly.

That is the realistic window for a cord left outside seasonally, even if you’re careful.

UV light is the main killer. Even “weather-resistant” jackets get brittle after a few seasons in the sun. Moisture works its way into cracks, then into the plugs. Temperature swings expand and contract everything, which accelerates the damage.

I would inspect any cord that has been through three full seasons. Look for cracking, stiffness, or corrosion on the prongs. If anything looks off, get a new one — a bad extension cord is a fire hazard that gets ignored because it still “works.”

For critical stuff like Christmas lights or a shop vac on a jobsite, do not push it past four years. Replace them on a schedule if you want to be safe.

This is not where you try to squeeze another season out of gear.