In a tradition as established as turkey curry on Boxing Day, swims were held across Wales, including Saundersfoot in Pembrokeshire, Barry, Vale of Glamorgan, and Abersoch in Gwynedd.
However, high winds meant the dip in Morfa Nefyn, Gwynedd, was cancelled.
Abersoch RNLI chairman, Phill Brown said the swim was "well supported by dippers and spectators alike".
Organisers of the Morfa Nefyn swim said it would be rearranged for Easter.
Barry organisers said between 400 and 500 people braved the cold water, with 1,856 taking part in Saundersfoot and a further 500 in Abersoch.
Saundersfoot Festivities chairman Martyn Williams said: "The village and wider community has done us proud again. We could not have conceived 33 years ago we would be here now hosting such a major event."
A spokeswoman for the swim in Barry said: "It was brilliant."
Thousands of hardy souls got their 2017 off to a chilly start with a New Year's Day swim in the seas around Wales.