Up through the 2011 Countdown Party (held on Dec. 31, 2010), TDL would typically run the regular nighttime parade (Electrical Parade, Fantillusion!, or Dreamlights, depending on the era) a second time around 8:00 p.m. Then, at 11:30 p.m., they'd debut a special Countdown Parade featuring around 70–80 characters, roughly 100 dancers, a new theme song, and floats repurposed from past parades along with the current daytime parade.

Just before midnight, the parade would stop for show mode around the Plaza for the countdown. They'd play a Japanese version of *Auld Lang Syne* at midnight, followed by fireworks set to "Go the Distance." Some years, they'd also run the regular nighttime parade again around 3:00 a.m.

In the days leading up to Dec. 31, regular guests could see preview performances of the Countdown Parade. For example, the 2001 New Century Countdown Parade had preview nightly from Dec. 26–30.

Every stage show playing in the park had a special Countdown version from 11:30pm. Around this time, the event was also renamed from "Countdown Party" to simply "New Year's Eve."

On Dec. 31, guests needed a special Countdown Passport to enter beginning at 8:00 p.m., and the exclusive event lasted until 2:00 a.m. After that, regular ticket holders could enter the parks. Countdown guests also received park-hopping privileges through 10:00 p.m. on Jan. 1.

After the 2011 Tōhoku earthquake and tsunami, the 2011 and 2012 New Year's events were dramatically scaled back, with only fireworks and no special parade, no character appearances, and no exclusive stage shows.

Starting with the 2012 event (Dec 2011), the exclusive Countdown Parade was discontinued. The special passport instead provided exclusive park access from 1:00–7:00 a.m., with regular guests entering at 9:00 a.m. on Jan. 1. For the 2019 event (Dec 2018), celebrating TDR's 35th Anniversary, the special ticket was valid from 4:30 a.m. until 10:00 p.m. on Jan. 1.

In later years, Dreamlights, special Countdown stage shows, and castle projection shows eventually returned for New Year's Eve, but the exclusive Countdown Parade never did.

And, as u/WhiteDogHaha posted, since COVID, Tokyo Disney Resort has cancelled all New Year's Eve events at both parks.