Arizona's 1st congressional district is a congressional district located in the U.S. state of Arizona, covering northeastern Maricopa County. Before 2023, geographically, it was the eleventh-largest congressional district in the country and included much of the state outside the Phoenix and Tucson metropolitan areas. From 2013 through 2022, it also included the Navajo Nation, the Hopi reservation, and the Gila River Indian Community, with 25% of the population being Native American. At that time, the district had more Native Americans than any other congressional district in the United States.^[4] In the 2022 elections, David Schweikert was elected in the redefined district. It was one of 18 districts that would have voted for Joe Biden in the 2020 presidential election had they existed in their current configuration while being won or held by a Republican in 2022.

The new 1st district includes northeast Phoenix, Scottsdale, Paradise Valley, Cave Creek, Carefree, and Fountain Hills; is majority-white; and is the wealthiest congressional district in Arizona.

When Arizona was first divided into congressional districts as a result of the 1950 census, the 1st district comprised all of Maricopa County, home to Phoenix, while the rest of the state was in the 2nd district. In a mid-decade redistricting resulting from Wesberry v. Sanders in 1967, the 1st was cut back to eastern Phoenix and most of what became the East Valley.

Over the years, the 1st's share of Phoenix was gradually reduced due to the area's explosive growth in the second half of the 20th century. However, it remained based in the East Valley until Arizona picked up two seats in the 2000 U.S. census. The old 1st essentially became the 6th district, while a new 1st district was created to serve most of the state outside of Phoenix and Tucson.

After the 2012 redistricting, the Hopi reservation was drawn into the 1st district; it had previously been included within the 2nd district. Also included were some northern suburbs of Tucson that had been in the 8th, as well as a tiny section of Phoenix itself near the Gila River Indian Community. Meanwhile, heavily Republican Prescott, the old 1st's largest city, and much of surrounding Yavapai County were drawn into the new, heavily Republican 4th district. The district is now considered to be significantly more competitive for Democrats, and now covers Northeastern Maricopa County, east of I-17 and north of Az-202 along the Salt River. It includes the northeastern suburbs of Phoenix, Scottsdale, Paradise Valley, Cave Creek, Carefree, Fountain Hills, Rio Verde, and the Fort McDowell Yavapai Nation.^[5][6] It is essentially the successor to the 2012–2021 6th district.^[7]

Arizona gained a second congressional seat after the 1940 census. It used a general ticket to elect its representatives until the 1948 elections, when candidates ran from each of the districts.

• Arizona's congressional districts
• List of United States congressional districts