A remodeler is planning to install a new 20-ampere branch circuit to serve a bathroom. The existing electrical panel has a 100-ampere main service. What is the maximum number of additional 20-ampere circuits that can be added?

Exam tip

Always check the existing load and the panel's rated capacity before adding new circuits.

Why B is correct

According to 2024 IRC 210.8(B), the total number of branch circuits in a panel cannot exceed 80% of the panel's rated capacity. Since the panel is 100-ampere, 80% is 80-ampere, leaving 20-ampere available for additional circuits. Therefore, two 20-ampere circuits can be added.