These are the saunas where the cold plunge is part of the design, not an afterthought. On-site tubs, troughs, or dip pools mean the hot–cold–rest cycle is available every session without planning the open-water swim yourself. Plan 90 minutes minimum to run the cycle properly rather than rushing a single long sit.
In Sydney, 6 of the curated saunas fit this cut. See the full Sydney guide for every venue, or keep scrolling for just the saunas with a cold plunge.
Every sauna with a cold plunge in Sydney

38° The Bathhouse
$$$Sydney, Australia
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Escape Bathhouse
$$$Sydney, Australia
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Nature's Energy Day Spa and Bathhouse
$$$Sydney, Australia
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Revive Wellness Centre
$$Sydney, Australia
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Sauna Amalfi Avalon
$$$Sydney, Australia
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The Sauna Hub
$$Sydney, Australia
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