My 89-year old grandmother is a Bulgarian citizen and a US green card holder. She wants to travel from the US to Bulgaria, connecting in Austria, but her Bulgarian passport has expired. Her Bulgarian ID card is permanent and valid. Will Austrian Airlines allow her to board her flight? Would she be allowed to enter Bulgaria with an expired passport but a valid ID card? Thank you in advance!
According to Timatic, the database used by airlines:
Travel without passport is possible for:
Nationals of Bulgaria with a national ID card.
Document validity rules:
Passports and other documents accepted for entry issued to nationals of Bulgaria must be valid on arrival.
So she should be OK to enter Bulgaria with just her national ID card. Transiting Austria will not involve immigration checks, so there is no problem there. She can use her green card to clear TSA identity checks in the US.
She doesn't need a passport at all, only a valid ID card.
To return to the US, she only needs her Green Card
So yes, she can fly there and back without a passport.
SOURCE (since Tomas By spreads false info based on loose interpretations of non-authoritative info):
Timatic, the IATA database used by Airlines, says:
Bulgaria: Passport Exemptions: Nationals of Bulgaria with a national ID card.
US: Passport Exemptions: Passengers with a Permanent Resident/Resident Alien Card (Form I-551).
So again, the simple answer is she does not need any passport at all whatsoever.
She should Show her green Card and Bulgarian ID when checking in for the flight to Bulgaria, then the Bulgarian ID when entering/exiting Bulgaria. When checking in for the flight to the US, as well as entering the US, she should Show her green Card.