The disclosure comes amid mixed quarterly results.
The company's shares, which fell as much as much as 4.7 percent in morning trade, pared most of their losses to trade down 0.3 percent at $307.77.
Profits dropped in the final quarter of 2018, but Tesla said it expected.
In the fiscal fourth quarter, the company's free cash flows increased to $910 million, better than the $881 million it had posted in the third quarter. Overall it is the fourth quarter that Tesla is announcing a profit since the 2010 IPO.
Since introducing the Model 3 three years ago, Tesla's difficulties have ranged from production snags to cash shortages to Musk's famously eccentric behavior.
Again, the Model 3 prove to be Tesla's most significant driver. It expects that Model Y production will cost even less.
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The model, who has more than 3.7million Instagram followers, became famous with a World Cup-themed advert for Beats By Dre in 2014.
Revenue beat expectations, at $7.23 billion, but the shares still slipped 1.1 per cent, or $3.27, to $305.50 in after-hours trading, reflecting investors' disappointment with the results.
"Barring unexpected challenges" with the planned factory in Shanghai, the company said, the added assembly lines could bring weekly Model 3 production to 10,000 sometime between October 2019 and June 2020. Both markets are considered important growth opportunities for the company. There is a method behind this madness: One battery type will further simplify production for Tesla, following similar variety-cutting efforts on the Model 3 months prior. Throughout 2018, Tesla delivered a total of 145,846 Model 3, making it "the best-selling premium vehicle (including SUVs) in the USA for 2018", says Tesla and thinks this will continue. Last year, the automaker attributed logistical problems to reports that lots full of Model 3s waiting for delivery inflated the automaker's claims of achieving 5,000 Model 3s per week.
In more concrete terms, Tesla is "expecting to deliver 360,000 to 400,000 vehicles" throughout 2019.
The electric auto maker reported a smaller fourth-quarter profit compared with the previous three months and said Model 3 production volume in California should reach 7,000 units per week by the end of the year.
The quarterly profit was less than half of the $311.5 million the company had earned in the three months to September.
That 500,000 annual target was originally expected to have been met in 2018.