Kiribati is among the first countries to celebrate New Year's Day because Kiritimati lies in the UTC+14 time zone.
Kiritimati, also called Christmas Island, is part of Kiribati's Line Islands. Its civil time is UTC+14, the world's most advanced standard time zone. As a result, midnight arrives there before it reaches most other inhabited places.
This arrangement dates from 1995, when Kiribati moved the International Date Line around its eastern islands so the country would share one calendar date. The change connected the Gilbert, Phoenix, and Line island groups administratively and economically.
Kiritimati is not the same place as Australia's Christmas Island, which is in the Indian Ocean and uses a much earlier time zone. News reports often simplify the fact by saying Kiribati is first, although the exact order depends on which inhabited islands and time zones are being compared.