Photos obtained by the Mail Online show the couple on the balcony of their jaw-dropping home, alongside guests including their close friends Jessica Rowe and Peter Overton.
WATCH: Keith Urban talks 16 years of marriage to Nicole Kidman
The apartment has a huge wraparound balcony with floor-to-ceiling glass doors from their spacious living area, where a dining table could be seen, providing the ultimate dinner party setting.
Nicole and Keith own three incredible apartments within the Latitude Building in Milsons Point, which overlooks Sydney Harbour.
First, they bought a $6million penthouse located on the 21st floor, before snapping up the penthouse next door for $7million in 2012, so they could combine the two into one enormous apartment.
Nicole Kidman's penthouse overlooks Sydney Harbour
Meanwhile, a $2.68million apartment on the 19th floor of the building was bought by Nicole in 2011, which she now reportedly uses as a home office.
Their apartments benefit from access to a heated pool, gym and sauna, as well as a prime location in Sydney, which Nicole showcased with her fans on Instagram on New Year's Day.
While she didn't give a glimpse of the New Year's Eve party itself, Nicole did share a photo of herself looking out over the Sydney Opera House the next morning, which she captioned simply: "New Year's Day."
Nicole and Keith also own another home in Australia
Nicole and Keith have spent the holidays in Australia with their daughters and had an emotional reunion shortly before Christmas after spending time apart while the actress filmed her new Amazon series, Expats, in Hong Kong.
The couple are clearly enjoying their time down under, and delighted fans with a surprise appearance at a kebab shop in Sydney after Christmas. Happily the lovers posed for a cute photo together sending fans absolutely wild. Nicole looked stunning in sunglasses and a beach hat while her husband Keith wore a baseball cap with his sunglasses clipped to his T-shirt.
The kebab shop posted the picture with the caption: "Our local legends always supporting us. #muchlove #nicolekidman #keithurban."
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