Area codes 208 and 986 are the telephone area codes designated for the entire state of Idaho in the North American Numbering Plan. The 208 code was one of the original 86 area codes introduced by the
American Telephone and Telegraph Company (AT&T) in 1947 and served as Idaho's only area code until 2017. Due to the increasing demand for phone numbers, especially with the rise of landlines, cellphones, and pagers in the 1990s, the 986 code was introduced in 2017 as an overlay to the existing 208 area. This introduction meant that Idaho residents could retain their existing numbers, and the new code would be used for new allocations. The transition to the new code included a period where both seven and ten-digit dialing were acceptable, but as of August 5, 2017, ten-digit dialing became mandatory across the state.
Idaho has the second-highest rate of adults who rely exclusively on mobile in the nation at 87.0%. Data from 2023 shows a gain of over 12 percentage points since 2019, when 74.9% of adults relied solely on mobile phones. Idaho adults who primarily use a wireless phone make up 8.0%, while 1.9% rely on both mobile and landline. Those who mainly rely on landlines and those who only use landlines have declined to 1.0% and 1.1% respectively. The share of adults lacking phone access stands at 1.0%. Idaho's rural geography has not slowed its embrace of mobile—the state now trails only Oklahoma in mobile-only adoption.