I need to go to Brazil on December 7th but just found out my Brazilian passport is expired. I have dual citizenship: Brazil and US. My US passport is valid. I have tried to schedule an appointment at the Brazilian consulate in Miami to renew my passport but the earliest date available is December 19th so that will not work. Would I be able to enter Brazil with my expired Brazilian passport and then re-enter the US with my valid US passport? Help, trying to figure this out ASAP!
As stated in Timatic, the database used by check-in staff at airports:
Nationals of Brazil are allowed to enter with an expired passport.
So your expired Brazilian passport is absolutely enough, and if check-in staff doesn't know this, tell them to check Timatic.
A valid Brazilian carteira de identidade is another option (listed in Timatic as well)
You can travel BACK to Brazil with an expired passport. Note that you do not need a valid passport to enter your own country. You simply need to prove identity and citizenship, which even an expired passport will do. That said, you are likely to experience an extended interview and delay upon returning.