The RNLI says they have over 1,500 lifeboat volunteers ready to drop everything if a call for help comes in this Christmas.
But they'd all prefer if their safety message got there first.
The Irish Coast Guard says 'stay back, stay high and stay dry.'
With Christmas swims scheduled across the region, the RNLI's Seán Dillon says a few precautions can go a long way – for both Christmas and New Year swims.
Firstly never swim alone, and remember that swimming in open water is very different from swimming in a pool. It’s colder, there may be unseen currents or waves.