Why is the trade deadline on August 31?

[nivshah]

Because it keeps more teams engaged for a longer percentage of the season, which is good for league health and also much more fun.

Here is a thread from a few years ago when I explored the idea of moving the deadline up to July 31:

2019 Trade Deadline

Hi all, our league is switching to H2H playoffs this year (the format where 4 teams make the playoffs and both rounds of the playoffs will last 2 weeks, so the playoffs will take up most of September). Wondering for those who used this format last year, did the Aug. 31 trade deadline affect the league standings down the stretch run. I fear that with the trade deadline so near the playoffs, a few tanking teams may have the ability to shift the league’s balance of power right before the playoffs. …