This is the most popular explanation. Back in Victorian England, rich folks would give their servants the day off on December 26th. It was the servants’ turn to visit their families. But wait—there’s more.
The masters would also hand out a “Christmas box.” This wasn’t a wrapped gift; it was a clay pot full of money and leftover treats. Think of it as a 19th-century bonus check.
Over time, churches got in on the act. They’d place an “alms box” by the altar during Advent. On the 26th, they’d open it and give the coins to the poor. Box + Day = Boxing Day. See? Not a single jab thrown.