The prototype built in Boca Chica, along the Gulf Coast of Texas, is nine yards (meters) in diameter - like the future rocket will be - but is shorter.
Its first test flights - suborbital "hops" reaching several miles (kilometers) in the air before landing back on Earth - could come in March or April.
An orbital prototype is expected in June. That version will be paired with a massive rocket booster known as the Super Heavy.
SpaceX has said the duo could some day transport people from city to city on Earth, as well as propel passengers around the Moon, to the lunar surface, and even to Mars and back.