Mr Carter said the trip would "develop people-to-people connections", including through business and trade, tourism, education, cultural exchanges and sport.
"Building on established relationships and creating new ones benefits our democracy and economy."
He said that the schedule was "fairly taxing". Such tours were immensely valuable, and played an important role in allowing MPs to observe how other democracies operate, Mr Carter told the Herald.
Last year's trip to Europe, which had a budget of $138,000 and saw four MPs spouses travel with them, was criticised by the Act Party as a junket.
MPs were able to downgrade from business class airfares and use the savings to help pay for their partners' travel, and any extra cost associated with partners must be met by the politicians.
This year only Ms Roche will be accompanied by her partner. Mr Carter will take his wife, and those costs will be met from the Inter-Parliamentary Relations Budget.
Speaker's tour
• April 19-29
• MPs: David Carter, Maurice Williamson (National), David Clark (Labour), Denise Roche (Greens), Mahesh Bindra (NZ First).
• Destinations: Mexico, Chile, Argentina
Itinerary
• April 19 - Arrive in Mexico City, dinner hosted by the Mexican Senate
• April 20 - Breakfast with Head of Mission, New Zealand Embassy in Mexico, meeting with ministries including foreign affairs, economy and agriculture. Attend folkloric ballet at the Palace of Arts.
• April 21 - Meet with Senators, Mr Carter will address the Senate, attend a function held at the New Zealand Residence.
• April 22 - Visit New Zealand sheep repopulation site, and attend an event with the State of Mexico.
• April 23 - Arrive in Santiago, Chile.
• April 24 - Welcome briefing with Head of Mission at New Zealand embassy, attend a dinner hosted by New Zealand Trade and Enterprise.
• April 25 - Anzac Day daw ceremony. Meeting with President of the Senate, the Minister of Agriculture, Education, Foreign Affairs and the Director General of Directorate of International Economic Relations.
• April 26 - Meet with the President of the Chamber of Deputies, meetings in the Congress, Mr Carter to deliver speech to local university.
• April 27 - Arrive in Buenos Aires, attend function with civil society leaders.
• April 28 - Welcome at Congress, meet parliamentary commissioners and other politicians, have lunch with members of Congress, and attend a trade and economic roundtable.
• April 29 - Meet with New Zealand businesses in Argentina, meet with a minister, lunch with the Governor of Province Santa Fe, meet with the Vice President of Argentina Amado Boudou.
