Both John Key and David Cunliffe are set to leave parliament in April.
The former Prime Minister will give his valedictory speech on March 22 and his resignation from parliament will take effect from April 14.
David will deliver his final speech on April 11, with his resignation effective from April 23.
“It has been an absolute honour to serve in Parliament since 2002, as MP for Helensville, National Party Leader, and Prime Minister,” says John.
“One of the great privileges of my political career and my life was to meet so many hard-working and inspiring New Zealanders. I remain as ambitious for them, and New Zealand, as the day I entered Parliament.
“I would like to thank all those who backed me and the National-led Government to build a stronger and more resilient country. We got New Zealand back on its feet, got people into jobs, got back into surplus, and tackled natural disasters."
John says he has enormous faith in the leadership team of Bill English and Paula Bennett to provide the "stability and continuity we need to build on that strength, while continuing to support those in need".
“I would also like to take this opportunity to thank my wife Bronagh, and my children Stephie and Max. I absolutely could not have done this job without their ongoing love and support.”
David sentiment is the same, saying "it's an enormous privilege to serve as a Member of the New Zealand Parliament and I have loved nearly every minute of it".
“In my time as MP for Titirangi from 1999-2002, as MP for New Lynn since then; and as a Minister of the Crown, senior Opposition spokesperson and as Leader of the Opposition, I have never forgotten the reason I came into politics and the reason that I'm passionate about the Labour Party.
“I believed then and now that all New Zealanders should have a right to reach their potential, regardless of race, job or gender; and that all our people are of equal worth and deserve equal respect, security and opportunity.
"As a Minister, I had a chance to do things that I hope will continue to make a difference, including helping Kiwis secure faster, cheaper telecommunications; better healthcare planning, more humane and focused immigration, better jobs in our regions, and a fairer tax system.
“I leave knowing that the Labour Party I care about is in good heart, well-led by Andrew Little and Jacinda Ardern, and with an able team of colleagues ready to make that difference for New Zealand in government.
"I've loved representing my electorate of New Lynn and the vibrant communities within it. I'm deeply grateful to my wonderful staff and members of the awesome New Lynn Labour Electorate Committee, who have stood solidly behind me through the ups and downs.
"I also want to express my deep gratitude to family and friends who have sustained and enabled me to serve during my term in Parliament.
"I'm excited about beginning a new chapter as part of the leadership team of management consulting firm Stakeholder Strategies Ltd, based in Auckland, where I'm looking forward to spending time with my sons William and Cameron, who continue to inspire me,” says David Cunliffe.