"First production cars will be handed over on Sept 29 at our Fremont factory," Musk said.
"With same options, Model X is $5k more than an S due to greater size & body complexity. Sig Series is fully loaded, hence high price," he wrote.
"Sig" is a reference to the top-of-the-line Signature Series. Tesla is now inviting Model X Signature reservation holders to configure their Model X. The Signature Series is an all-wheel-drive model with a 90 kWh battery.
The Signature Series is a fully loaded Model X with special badging and will be delivered before the automaker begins delivering the standard Model X, said Tesla spokeswoman Khobi Brooklyn in response to a query from Edmunds on Wednesday.
The Model X Signature starts at $133,200, including a $1,200 destination charge.
Brooklyn said Model X pricing and specifications listed recently on Tesla enthusiast Web sites is correct.
He added: "Fully operational Gigafactory needed."
The Gigafactory is Tesla's lithium-ion cell fabrication and battery-assembly plant under construction in Nevada.
In another tweet, Musk said confirmed Model 3 pricing and pre-orders.
"$35k price, unveil in March, preorders start then," he wrote.
Edmunds says: Tesla's lineup is beginning to expand, which is good news for shoppers seeking electric vehicles.