Alltel Corporation was, until its acquisition by Verizon Wireless, the fifth largest wireless telecommunications company in the United States with 14.7 million customers, as of the fourth quarter 2008, behind AT&T Mobility, Sprint-Nextel, and T-Mobile.

At its peak, Alltel operated a network in 34 states, with a wireless coverage area comprising the largest network in the United States by area. The company focused on small to medium size cities providing wireless services to residential and business customers in all 50 states through low-cost roaming agreements with the major national CDMA carriers including Verizon Wireless and Sprint Nextel. These agreements gave Alltel customers access to nationwide service while providing those carriers coverage in rural areas.

On June 5, 2008, Verizon Wireless announced it would acquire Alltel Wireless in a deal valued at $28.1 billion. The merger was approved by the FCC on November 4, 2008, and completed on January 9, 2009. With this merger, Verizon Wireless now has approximately 83.7 million wireless subscribers and covers nearly the entire United States population making it the largest network in the country by area covered and number of subscribers. However, 2.1 million of these customers will soon be divested, per the conditions of FCC and DOJ approval of the merger.

The complete integration of the non-divested Alltel markets into Verizon Wireless should be completed by 3rd Quarter 2009.

On 8 May 2009, AT&T announced that it will buy Alltel divestments from Verizon in the western states including Montana, parts of Wyoming, North Dakota and South Dakota. The FCC will vote on this deal in October 2009. But Alltel divestment markets in other states that AT&T will not buy are still up for bidding. Companies bidding for these areas are mostly private investment compaines. But customers in these areas should know by the end of May 2009 what their next wireless company will be. Customers in the western states – said to number around 1.5 million – now know their next wireless company will be AT&T.

Alltel's modern history begins in 1983 when Allied Telephone and Mid-Continent Telephone merged. Mid-Continent Telephone was founded by Weldon W. Case and his younger brother, Nelson H. Case. The elder Case became Alltel's first chairman and headquartered the company in Hudson, Ohio. In 1985, Alltel launched its first wireless system in Charlotte, North Carolina. In 1993, Alltel opened its first wireless retail store. In 1997, the company's wireless and wireline businesses were combined into a single organization.

On December 9, 2005, Alltel announced that it would become a wireless-only company, simultaneously merging and building a spin-off company for its wireline services. The wireline services business of Alltel merged with Valor Telecom and was named Windstream Communications on April 10, 2006. The merger-spinoff process ended July 17, 2006 when Windstream began operations.