Luxon challenged the PM on the Government's record since 2017, bringing up the controversial Kiwibuild programme that promised 100,000 homes in 10 years but had so far delivered 1.3 per cent.
He also brought up the huge increase in demand for social housing, which he said had gone up "360 per cent" since Labour took office.
Ardern said since taking office each Budget had been "unapologetically" focused on the cost of living. Labour had built 9000 social houses she said, in stark contrast to National's time in government when it sold social houses.
Ardern said the Government had also expanded free and low-cost doctor visits, community service card access and warmer winter initiatives. The Government had also made progress on RMA reform and there were record housing consents, she said.
Luxon also brought up the Auckland light rail, originally meant to be built two years ago but still awaiting a business plan, school attendance rates and where the $1.9 billion mental health investment from 2018 had gone.
The Mental Health and Wellbeing Commission found this year that despite the investment and improvement in primary care, there had been little change in access to specialist mental health services.
Ardern said the economic crisis brought on by the pandemic "not seen in 100 years" had affected projects, and yet GDP was up and unemployment "the lowest on record".
She compared this to how National had fared post the Global Financial Crisis.
Question Time is the last ahead of the Budget – and Ardern beamed in from Premier House via the remote Parliament system after leaving it to Deputy Prime Minister Grant Robertson and Minister Megan Woods to help fill in for her while she was ill.
It is a sign she is now on the road to recovery after being too unwell to take part in events earlier in the week, and will be able to deliver a speech during the Budget debate tomorrow.
The PM also faced questions from Act leader David Seymour.
Meanwhile, National's deputy leader and finance spokeswoman Nicola Willis challenged Finance Minister Robertson over the choice to reform the health system with a "record spend-up" at a time of such economic uncertainty.
"I will never have a regret about properly funding our health system so that New Zealanders have the health services they need and deserve wherever they live," Robertson said.
"I will never regret making sure we reduce decades of inequalities for Māori and Pacific health outcomes and I will never regret coming to this House to make sure that the National Party never get their hands on the health system again."
Ardern announced on Saturday that she had tested positive for Covid-19 nearly a week after her household went into isolation because her partner Clarke Gayford got it. Their daughter, Neve, had also caught it by last Wednesday.
Ardern had reported she had "moderate symptoms" - and had not been able to deliver a speech by Zoom at the Government's unveiling of its climate change Emissions Reduction Plan on Monday or take part in Question Time on Tuesday.
Ardern will not be able to attend tomorrow's Budget - her isolation period ends on Saturday morning - but can speak remotely during the debate on it.
However, her office has confirmed that her Budget day tradition of buying a new tie for Finance Minister Grant Robertson will take place - and Ardern and Robertson will also share their traditional cheese rolls morning tea by Zoom after a contactless delivery to Premier House.
National MPs are also asking questions of ministers about the cost of living, a mental health announcement and on law and order today. Green Party MP Teanau Tuiono will ask about the Emissions Reduction Plan.
