What is the difference between financial independence and early retirement in FIRE?

They are two separable milestones. Financial independence (FI) means your investments can cover your living expenses indefinitely, so paid work becomes optional. Early retirement (RE) is the choice to actually stop full-time work once you reach FI. You can have one without the other.

Many people who reach FI keep working because they enjoy it, want extra buffer, or fear boredom; they are financially independent but not retired. Others retire early on a leaner cushion and rely on flexibility or part-time income. Framing FI as the real goal and RE as an option relieves the pressure to quit the day you hit your number. It also explains variants like Coast and Barista FIRE, which are really different mixes of independence and continued work.