Nicholls was a member of the New Zealand team that won the 2019–2021 ICC World Test Championship.

In December 2015, Nicholls was named in New Zealand's One Day International (ODI) squad for their series against Sri Lanka.

[2] He made his ODI debut on 26 December 2015 at Hagley Oval, Christchurch, which is his home ground for Canterbury.

[5] In February 2016, Nicholls was added to New Zealand's squad for the 2016 ICC World Twenty20 tournament, also as a backup wicketkeeper to Luke Ronchi.

[15][16] In November 2023, Nicholls was reported to New Zealand Cricket for an issue surrounding ball tampering during a Plunket Shield fixture between Auckland and Canterbury.