A few preliminary comments:

• Only 3 of these peaks lack an official name.
• Some county high points are merely waypoints on a rise to a higher summit in another county. Every point on this list is a peak and all of them are ranked summits.
• The county boundaries I used come from a repository used by Google so they may not be as precise as needed to get a truly accurate list.
• The list includes some more iconic mountains in place of less iconic high points.
• In my home county of Ada, the most prominent peak is Shaw Mountain but the high point is the Boise Ridge South Summit. For Camas County, the most prominent peak is highly-visible Smoky Dome instead of the summit just south of Bromaghin Peak.
• The list includes all of Idaho’s ultra-prominent peaks.
• Some truly iconic Idaho summits (like Bell Mountain) are not present in the prominence list but they do appear in the high point list.
• Likewise, the most prominent mountain in Boise County seems to be Shafer Butte but the high point (Mount Cramer) is much more representative of the Boise County mountain experience.
• Two of the peaks (the peaks in Canyon County and Lewis County) are located on private property and access is unknown.
• Corrections for any errors are always welcome.

Ada             – Shaw Mountain (5908, 1124)

Adams        – Council Mountain (8131, 2323)

Bannock     – Sedgwick Peak (9170, 3647)

Bear Lake   – Meade Peak (9957, 2485)

Benewah     – Lindstrom Peak (4695, 1679)

Bingham     – East Butte  (6575, 1543)

Blaine          – Hyndman Peak (12009, 4837)

Boise           – Shafer Butte (7582, 2715)

Bonner        – Scotchman Peak (7025, 4663)

Bonneville   – Caribou Mountain (9816, 3098)

Boundary    – Boundary County High Point  (7712, 3317)

Butte            – Diamond Peak (12197, 5375)

Camas         – Smoky Dome (10097, 3268)

Canyon        – Walters Butte (2938, 464) —Private Property

Caribou       – Bonneville Peak (9271, 3395)

Cassia         – Cache Peak (10339, 4493)

Clark           – Big Table Mountain  (9083, 1896)

Clearwater  – Rhodes Peak (7932, 2698)

Custer         – Borah Peak (12662, 5982)

Elmore        – Trinity Mountain  (9459, 2381)

Franklin       – Oxford Peak (9307, 4042)

Fremont      – Mount Two Top (8700, 1622)

Gem            – Squaw Butte (5896, 1718)

Gooding      – Windy Benchmark (5926, 388)

Idaho           – He Devil  (9420, 5230)

Jefferson     – Table Butte  (5235, 336)

Jerome        – Flat Top Butte (4297, 369)

Kootenai      – Mica Peak (5252, 2669)

Latah           – Bald Mountain (5340, 2117)

Lemhi          – Scott Peak  (11398, 4251)

Lewis           – Peak 3460 (Greer Hill)  (3460, 450) —Private Property

Lincoln         – Dietrich Butte (4635, 432)

Madison       – North Menan Butte (5619, 790)

Minidoka      – Kimama Butte (5077, 776)

Nez Perce    – Craig Mountain (5372, 1057)

Oneida         – Elkhorn Peak (9097, 3498)

Owyhee       – Hayden Peak (8417, 3150)

Payette        – Peak 3326 (Bannister Hill) (3326, 492)

Power          – Deep Creek Peak (8751, 3242)

Shoshone    – South Butte (6994, 2373)

Teton           – Piney Peak (9021, 2250)

Twin Falls    – Peak 6787 (Mule Creek Butte)  (6787, 917)

Valley           – Big Baldy (9705, 3200)

Washington  – Sturgill Peak  (7589, 3434)