Air New Zealand has round-trip flights from Houston (IAH) to Auckland (AKL) for $803, NONSTOP. Flights from April to September and November to December. No minimum stay requirement.
Note: Pay attention to the Time, Date, and Season change while traveling.
Note: This is also available for about -$70 less if you add a stop on the return flight. Doing so will add about 7-hours to your total travel time. If you value your time at greater than $10 an hour then you’ll probably want to avoid adding the stop.