'Tis the season for homes decked out with Christmas lights. But all of that holiday spirit comes at a price: In California and New Hampshire, it can add nearly $30 to your electricity bill to run lights from Thanksgiving to New Year's. In other states, it could be even more.

Deal site Simple Thrifty Living determined the average amount it costs to light a Christmas display for 34 days — from Thanksgiving to New Year's — for six hours a night in each U.S. state. The calculations accounted for 10 strands of incandescent lights, 68.5 feet long each, plus two inflatables. Here's a closer look at the methodology.

Overall, it costs an average of $19.81 to light up a Christmas display in the U.S. Powering these festive decorations is most expensive in Hawaii at $46.62 for 34 days and least expensive in Louisiana at just $13.94. The biggest expense is the lights, as the inflatable decor doesn't cost much more than $1 in most states.

Source: Simple Thrifty Living

Here's a closer look at how much it costs to light up your home for Christmas from Thanksgiving through New Year's Day in every U.S. state.