First Night of a Holiday:

Candles may be lit before or after sunset. If the candles are lit after sunset, they must be lit from a pre-existing flame.

If the first night of the holiday is Friday night, then the candles must be lit before sunset.

If the first night of the holiday is Saturday night, then the candles must be lit after the conclusion of Shabbat.

Second Night of a Holiday:

The candles are lit after nightfall from a pre-existing flame.

If the second night of the holiday is Saturday night, one must wait until the conclusion of Shabbat before lighting the candles.

If the second night of the holiday is Friday night, the candles are lit before sunset, also from a pre-existing flame.

Click here for the times of sunset, nightfall, and end of Shabbat in your area.