How long does iwatch 4 battery last

My Series 4 Apple Watch is 3 years and 2 months old.

I put it on my wrist this morning about 13 hours ago, and I currently have 57% battery remaining.

My Apple Watch mostly leads a life as a watch. That is say, I rarely make or receive phone call on it (except for SPAM calls, which I just send to voice mail). I do not stream music. The most I do is take an hour walk every day, so the Outside Walk exercise app is running along with the GPS for that hour.

Otherwise, I look at the weather, use the MyQ app to open and close the garage door before and after my walk, but I do not do much else.

Also it is always near my iPhone, so it rarely needs to use any radio except the low energy Bluetooth radio.

That will depend on usage. Mine is about two years old and close to needing to be replaced. Your mileage may vary.

See here;

watch Repair

And here;

watch Service Pricing

Apple says about 18 hours with average use.

Check your battery health in settings if it's near 80% then its recommended to replace the battery.

Settings/battery/battery health