There is a "paint-by-number" setup so the jerseys match the League's official jersey template, and a note section so fans can explain their design choices.
Entries can be submitted up to July 24, and from there five finalists will be selected and those five jerseys will then be put up to a fan vote in August.
"Islanders fans are among the most passionate in all of sports, and their emotional investment is the heartbeat of this franchise," said Kelly Cheeseman, president of business operations for the Islanders and UBS Arena. "With this contest, we are breaking down traditional boundaries and inviting ‘Isles Nation' directly into the design room to do something that has never been done before in our league.
"Our third jersey will truly belong to the fans, born from their passion and chosen by their voice."
The jersey that wins the fan vote will become the Islanders official third jersey for 2027-28, and the winning creator will get a signed third jersey and tickets for the game when the jersey makes its debut.