Jim Butcher's most productive writing hours run overnight, and the schedule around them was built to coexist with another working novelist under the same roof.

The Direct Answer
Midnight to dawn, once his wife has gone to bed.
Under deadline pressure, Butcher has described waking around noon, close to when novelist Shannon K. Butcher finishes her own workday.

Two Writers, Opposite Shifts

Butcher's wife, Shannon K. Butcher, is a novelist too, and their household runs on a kind of shift work. Shannon does her most productive writing in the morning and early afternoon. Butcher does his best work between midnight and dawn. When a deadline is close, his day starts around noon, right about when Shannon is wrapping up her own working hours.

They spend the afternoon and evening on errands or together, and once Shannon goes to bed, Butcher sits down to write. Neither schedule interrupts the other because the working hours simply don't overlap, which solves a problem a lot of two writer households never quite figure out: how to give two people the same quiet house without either one giving up their best hours.

Why the Hour Fits the Work

Harry Dresden's Chicago is a night city, and writing that world between midnight and dawn, when Butcher's own house has gone quiet the same way, lines up with the material in a way that's hard to dismiss as coincidence. A writer describing three in the morning tends to sound more convinced when three in the morning is also when he's at the keyboard.

For more on how this schedule connects to the outline Butcher still uses and the craft philosophy behind eighteen Dresden Files novels, see the complete Jim Butcher writing routine.

What You Can Steal