The 20th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1951, to December 31, 1952, during the first two years of John Howard Pyle's term as Governor of Arizona. The number of senators remained constant at 19, while the members of the house of representatives increased from 58 to 68. The Democrats controlled one hundred percent of the senate, while in the house the Democrats increased six seats and the Republicans gained four seats, giving the Democrats a 57–11 edge.
The 22nd Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1955, to December 31, 1956, during the first of two terms of Ernest McFarland's time as Governor of Arizona. The number of senators was increased to two per county, for a total of 28, while the members of the house of representatives increased from 80 to 81. The Republicans lost two Senate seats, leaving the Democrats in control of the upper house with a 26–2 margin. In the House, the Republicans lost ten seats, while the number of seats controlled by the Democrats increased by eleven, giving the Democrats a 61–20 edge.
The 23rd Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1957, to December 31, 1958, during the second of two terms of Ernest McFarland's time as Governor of Arizona. The number of senators remained constant at two per county, totaling 28, while the number of members of the House of Representatives decreased from 81 to 80. The balance in the upper house continued at a 26–2 margin in favor of the Democrats. In the House, the Republicans picked up three seats, while Democrats lost four seats, however the Democrats still held a 57–23 edge.
The 24th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1959, to December 31, 1960, during the first of three terms of Paul Fannin's time as Governor of Arizona. The number of senators remained constant at two per county, totaling 28, and the members of the house of representatives also held steady at 80. The Democrats picked up a seat in the upper house, increasing their edge to 27–1. In the House, the Republicans picked up three seats, however the Democrats still held a 55–25 edge.
The 25th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1961, to December 31, 1962, during the second of three terms of Paul Fannin's time as Governor of Arizona. The number of senators remained constant at two per county, totaling 28, and the members of the house of representatives also held steady at 80. The Republicans picked up three seats in the upper house, but the Democrats still had a 24–4 edge. In the House the Republicans picked up two seats, leaving the Democrats with a 52–28 edge.
The 26th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1963, to December 31, 1964, during the last of three terms of Paul Fannin's time as Governor of Arizona. The number of senators remained constant at two per county, totaling 28, and the members of the house of representatives also held steady at 80. The Democrats maintained a 24–4 edge in the upper house, while the Republicans gained four seats in the House, trimming the Democrats majority to 48–32.
The 27th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1965, to December 31, 1966, during Samuel Pearson Goddard Jr.'s only term as Governor of Arizona. The number of senators remained constant at two per county, totaling 28, and the members of the house of representatives also held steady at 80. The Democrats picked up two seats in the Senate, giving them a 26–2 edge in the upper house, while the Republicans gained three seats in the House, trimming the Democrats majority to 45–35.
The 28th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1967, to December 31, 1968, during Jack Williams' first term as Governor of Arizona. The make-up of both houses was changed drastically by the implementation of districts, rather than the old system of county representation. The fourteen counties were broken up into 8 districts. Four of the districts consisted of multiple counties, while the other four represented single counties. In addition, Districts Seven and Eight, representing Pima and Maricopa Counties respectively, were further broken down into sub-districts. District 7 had eight sub-districts, 7-A through 7-F, while District 8 had fifteen sub-districts, 8-A through 8-O. The number of senators increased to 30, with the balance of power shifting drastically. Where Democrats had held a 26–2 majority in the prior legislature, Republicans now held a slim 16-14 majority. While the number of senators increased, the number of representatives decreased from 80 to 60. Again, the balance of power shifted to the Republicans, who now held 33-27 majority in the lower house. It was the first time Arizona history where the Republicans won control of both houses of the legislature.
The 29th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1969, to December 31, 1970, during Jack Williams' second term as Governor of Arizona. The number of senators remained constant at 30, and the members of the house of representatives also held steady at 60. The Republicans picked up a single seat in the Senate, giving them a 17–13 edge in the upper house, and the Republicans also gained one seat in the lower house, increasing their margin to 34–26.
The 33rd Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1977, to December 31, 1978. The legislature met during the terms of three Arizona Governors. When it was constituted, Raúl Héctor Castro still had two years remaining on his only term in office as Governor of Arizona. When Castro left the office to become Ambassador to Argentina in October 1977, he was succeeded by Wesley Bolin, Arizona's Secretary of State. Arizona's constitution mandates that the Secretary of State is first in line of succession to the office of Governor. However, Bolin died in office five months later, on March 4, 1978, and was succeeded by Bruce Babbitt, who was then the Attorney General. Bolin was not succeeded by his replacement, Rose Mofford, because she had been appointed, not elected to the office. Succession fell to the next in line, Babbitt. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Republicans made inroads into the Democrat lead in the Senate, picking up two seats, although the Democrats maintained a 16–14 edge in the upper house. In the lower chamber, the Republicans increased their majority by 5 seats, giving them a 38–22 margin.
The 36th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1983, to December 31, 1984, during the first two years of Bruce Babbitt's second full term as Governor of Arizona. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Republicans increased their lead in the Senate by two seats, giving them an 18–12 edge in the upper house, while the Democrats gained four seats in the lower house, although the Republicans still held a 39–21 majority.
The 38th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1987, to December 31, 1988, during the two years of Evan Mecham's term as Governor of Arizona, and the first year of Rose Mofford's term as governor after Mecham's impeachment. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Republicans gained a seat in the Senate, giving them a 19-11 majority, while the Democrats gained to seats in the house, decreasing the Republican majority to 36–24.
The 39th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1989, to December 31, 1990, during the last two years of Rose Mofford's term as governor. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Democrats gained two seats in the Senate, cutting the Republican majority to 17–13, and the Democrats also gained a seat in the house, decreasing the Republican majority to 35–25.
The 40th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 1991, to December 31, 1992, during the first two years of Fife Symington's first term as governor. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Democrats flipped control in the Senate, gaining four seats and creating a Democratic majority of 17–13. The Democrats also gained two seats in the house, decreasing the Republican majority to 33–27.
The 45th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 2001, to December 31, 2002, during the final two years of Jane Dee Hull's first full term in office. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Republicans lost a seat in the Senate, creating a 15-15 balance with the Democrats. The Republicans lost four seats in the House, maintaining their majority in the lower chamber, 36–24.
The 46th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 2003, to December 31, 2004, during the first two years of Janet Napolitano's first term in office. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Republicans gained two seats in the Senate, giving them a 17-13 majority. The Republicans gained four seats in the House, maintaining their majority in the lower chamber, 39–20-1, with a single representative switching their party affiliation from Democrat to Independent after the election.
The 47th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 2005, to December 31, 2006, during the second two years of Janet Napolitano's first term in office. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Republicans gained a seat in the Senate, giving them an 18-12 majority. The Republicans maintained their majority in the lower chamber, 39–21, while the Democrats picked up the sole seat held by an Independent.
The 48th Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 2007, to December 31, 2008, during the first two years of Janet Napolitano's second term in office. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Democrats gained a seat in the Senate, leaving the Republicans with a 17-13 majority. The Republicans maintained their majority in the lower chamber, 33–27, even though the Democrats picked up 6 seats.
The 51st Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 2013, to December 31, 2014, during the last two years of Jan Brewer's first full term in office. Both the Senate and the House membership remained constant at 30 and 60, respectively. The Democrats gained five seats in the Senate, decreasing the Republican majority to 16–14. The Democrats also gained four seats in the lower chamber, leaving the Republicans with a 36–24 majority.
The 53rd Arizona State Legislature, consisting of the Arizona State Senate and the Arizona House of Representatives, was constituted in Phoenix from January 1, 2017 to December 31, 2018, during the second two years of Doug Ducey's first full term in office. Both the Senate and the House membership remained constant at 30 and 60, respectively. Democrats gained one seat in the Senate, leaving the Republicans with a 17-13 majority. Republicans also maintained an 35–25 majority in the House after losing one seat to the Democrats.
