The $US7500 ($A11,558) tax credit had been a driver of EV sales, and the industry is bracing for a drop in demand through the rest of the year. Tesla did not provide a full-year forecast.
"While we face near-term uncertainty from shifting trade, tariff and fiscal policy, we are focused on long-term growth and value creation," the company said in a shareholder update on Wednesday.
Shares of the Austin, Texas-based company were down about 2.0 per cent in extended trading.
The electric vehicle maker reported total revenue of $US28.1 billion ($A43.3 billion) for the third quarter ended September 30, compared with analysts' average estimate of $US26.37 billion ($A40.64 billion), according to data compiled by LSEG.
Profit per share in the third quarter was 50 cents, below analysts' estimates of 55 cents.
Tesla reported gross margin of 18 per cent, compared with estimates of 17.5 per cent. Its closely watched automotive gross margin, excluding regulatory credits, was 15.4 per cent, compared with an average estimate of 15.6 per cent, according to 19 analysts polled by Visible Alpha.
Tesla's limited rollout of its self-driving "robotaxi" service in Austin, Texas, earlier this year marked a key strategic pivot, underpinning investor expectations that the company will transition from pure vehicle sales to focusing on self-driving technology.
While most of Tesla's current revenue is still derived from vehicle sales, its $US1.45 trillion ($A2.23 trillion) valuation largely reflects investor bets on robotics and AI.
Tesla introduced lower-cost "Standard" variants of Model Y and Model 3 vehicles earlier this month as part of a volume-growth push, cutting features and prices to make the vehicles more accessible after the expiration of the US tax credit on EV purchases.
A rush in the US to grab the federal incentive before it went away at the end of September resulted in the company delivering a record number of vehicles in the third quarter.
While Tesla hopes the cheaper variants will drive higher volumes, analysts warn the move will squeeze margins as thousands of dollars of cost cuts per vehicle may not fully compensate for lower selling prices.
Wall Street expects Tesla's deliveries in 2025 to fall 8.5 per cent due to the expiry of the tax credit, reliance on older models and rising competition. Tesla CEO Elon Musk's embrace of right-wing politics has also alienated some potential buyers.
Tesla is banking on the rollout of its lower-cost standard variants to revive volume growth, though some analysts remain sceptical of a strong rebound as the cheaper version could take away sales of more profitable premium vehicles.
For years, Tesla has benefited from selling regulatory credits to other automakers as they worked to comply with emissions or zero-emission vehicle mandates, representing a meaningful supplemental revenue stream.
That tailwind is rapidly fading. US policy changes are expected to reduce this income stream significantly, and analysts now estimate revenue for the highly profitable regulatory credits could fall dramatically in the coming quarters.
