What
A player-run group.
A fleet can contain up to 500 player characters and provides shared fleet systems such as ranks, fleet chat, a fleet bank and fleet holdings.
Star Trek Online · Answers · Fleets ·
-PTF- Answers
What is a fleet in Star Trek Online and how do you join one?
A fleet is Star Trek Online's player guild system. Fleets are player-run groups with ranks, chat, a shared bank and progression through fleet holdings. To join one, your character needs a fleet invitation and you accept it in-game.
Direct Answer
A fleet is STO's version of a guild
How to join
Receive and accept a fleet invite.
Find a fleet you want to join and ask a member with invite permission to invite your character. Accept the invitation in-game and that character joins the fleet.
Fleet system reference: STO Wiki — Fleet (opens in new tab)
Membership
Fleet membership belongs to the character
Joining with one character does not automatically add your other characters.
Characters
Membership is per character.
A fleet roster is made up of individual player characters rather than whole accounts. The character that accepts the invitation is the character that joins.
What Fleets Provide
Why join a fleet?
Shared systems
Chat, ranks and a fleet bank.
Fleets have their own roster, rank structure, chat and shared bank, with permissions controlled by the fleet's ranks.
Holdings & stores
Progression can unlock fleet equipment.
Members can contribute to fleet projects and holdings. Developed holdings can provide access to fleet equipment, ships, services and other items, subject to the fleet's progression and permissions.
Full Reference
Want the full fleet system?
STO Wiki
Fleet holdings, levels, banks and Armadas.
The STO Wiki's Fleet page covers the deeper mechanics, including fleet advancement, holdings, fleet levels, banks, creation requirements and Armadas.
Sources checked: STO Wiki — Fleet (opens in new tab)