Yes, it has an A4 drawer and a drawer that you can load with A4 or A3 as well as a manual feeder for A4 and A3. Great machine and instantly connectable to Mac.

Does the A3 drawer close completely when filled with A3 or does it stay halfway out like on certain Brother models?

Yes, exactly:
Even A3+ fits in the manual feeder.
Great machine and value for money and easy to install/operate as well as fully network and wifi enabled.
2 disadvantages:
- Scanning documents is very slow.
- Device ejects copies/prints sorted by pages but unfortunately not (yet) by "sentences",
i.e. e.g. 3 copies of a 10-page text are sorted by pages 1-10.
but just all copy sets on one another.
Greetings Bruno