You generally need your March Madness bracket filled out before the first game of the main tournament tips off , not just “sometime on Thursday.”

Quick Scoop: Key Deadline

  • For 2026 online contests, most sites are using:
    • Men’s tournament: brackets due by around 12:00–12:30 p.m. ET on Thursday, March 19.
* Women’s tournament: brackets due by late morning to 12:30 p.m. ET on Friday, March 20.
  • After the first Round of 64 game starts, brackets lock and you usually can’t edit or submit a new one.

In most office pools or online games (ESPN, CBS, Yahoo, NCAA.com), the rule is the same:

Entries must be completed before the first game’s tipoff for that tournament.

Why it feels stressful (and how people handle it)

  • The bracket only really opens after Selection Sunday , when the full field and matchups are announced.
  • That gives you just a few days to:
    1. Skim expert picks and injury news.
2. Debate your potential “Cinderella” upsets with friends or on forums.

3. Second‑guess everything right up until Thursday morning.

A lot of fans push it right to the edge of the deadline, which is why sites warn about possible slowdowns and recommend locking in your bracket a bit early to avoid tech glitches.

A few practical tips

  • Check the specific rules of:
    • Your office/friends pool (they might have their own earlier cut‑off).
* Whatever site/app you’re using (ESPN, CBS, Yahoo, NCAA.com each post their exact lock time).
  • Assume: “Once the first real Thursday game starts, I’m done.” That’s the safest mental rule.

TL;DR: Have your bracket filled out and submitted no later than just before the first Thursday game of the tournament tips off (and Friday for women’s), and check your specific pool/site for the exact timestamp.

Information gathered from public forums or data available on the internet and portrayed here.