Do prelit trees use much electricity ?

Not really, but it depends on what your utility company charges and is your house lit up like a Las Vegas Casino? If the tree is the bulk of your holiday decor that requires electricity and you run it a few hours every night, you should not notice much of a difference. Here are some links.

https://www.christmaslightsetc.com/pages/how-much-power.htm

https://www.wired.com/2012/12/how-much-does-it-cost-to-power-your-christmas-lights/

https://cashmoneylife.com/christmas-lights/

I do the bulk of my holiday decor outside and do a lot of lights and holiday tradition in this neighborhood is to turn them on for the first time on Thanksgiving night through New Year's Day. Even burning 6 hours or so a night, the extra cost (for me) is just a few extra dollars. Again it depends on what your utility company charges.

No it never did mine. Actually one year i outline my ceilings in my house with Christmas lights and used them rather than lamps and my electric bill dropped 30 a month

No...the pre-lit trees do not use a lot of electricity. ...especially if you get the kind that has LED lights. They use a lot less power than the old large bulbs.

if they have LED bulbs you’re good. Otherwise they can spin the hand on that meter.

The newer trees have led lights that do not use much electric

No more than the regular lights. If you are worried about your december electric bill, keep all of you lights off except for a couple hours in the evening. We have lots of lights on the porch and inside and our bill goes up about $50 but I leave the tree lit all day.

Thank you