The Tata Aeris CNG delivers an ARAI-certified mileage of 26.49 km/kg with the 5-speed manual gearbox and 28.06 km/kg with the 5-speed AMT automatic. It uses a 1.2-litre, 3-cylinder petrol engine converted to run on factory-fitted twin-cylinder CNG technology, paired with a 70-litre CNG tank. The Aeris was launched in India on September 25, 2026, starting at Rs 5.29 lakh (ex-showroom) for the base petrol variant, with CNG versions priced roughly Rs 1 lakh higher.
Tata Aeris CNG Mileage Figures at a Glance
| Variant | Transmission | ARAI Mileage | Fuel |
|---|---|---|---|
| Aeris CNG | 5-speed Manual | 26.49 km/kg | CNG |
| Aeris CNG | 5-speed AMT | 28.06 km/kg | CNG |
| Aeris Petrol | 5-speed Manual | 19.2 km/l | Petrol |
| Aeris Petrol | 5-speed AMT | 19.2 km/l | Petrol |
The Aeris CNG carries forward the same 1.2-litre Revotron engine and dual-cylinder CNG setup used on the outgoing Tata Tigor, so its certified mileage numbers are directly comparable and confirmed at launch rather than pre-launch estimates.
Why the AMT Version Gets Better CNG Mileage Than the Manual
It may seem counterintuitive that the automatic variant returns higher mileage than the manual, but this pattern is common with AMT gearboxes. The AMT shifts at more consistently optimal engine speeds than an average driver managing a clutch, which reduces unnecessary revving and improves fuel-conversion efficiency, especially on CNG where the combustion characteristics are more sensitive to engine load and RPM consistency.
Engine and CNG Tank Specifications
The Tata Aeris CNG uses a 1199cc, 3-cylinder petrol engine tuned for bi-fuel operation, producing around 72 to 72.5 PS of power and roughly 96.5 Nm of torque on CNG mode, slightly lower than its petrol-only output due to the nature of gaseous combustion. It features a 70-litre water-capacity CNG tank built using Tata’s twin-cylinder technology, which frees up more usable boot space compared to a conventional single large cylinder. The car also supports direct CNG start, meaning the engine can be cranked straight on CNG mode without switching over from petrol first, a convenience feature that also indirectly helps preserve real-world mileage by avoiding a petrol-heavy cold start every time.
Real-World CNG Mileage: What to Expect
ARAI figures are measured in controlled laboratory test conditions, so real-world mileage on CNG will typically be somewhat lower depending on driving style, traffic conditions, air-conditioning use, and load. Based on how comparable Tata CNG models perform on Indian roads, Aeris CNG owners can realistically expect:
City driving: approximately 20 to 23 km/kg, accounting for stop-and-go traffic and idling.
Highway driving: approximately 24 to 27 km/kg, closer to the ARAI-rated figure due to steady speeds and lower engine load variation.
Mixed driving: approximately 22 to 25 km/kg for most daily commuters combining city and highway use.
These are practical estimates and will vary from car to car and driver to driver.
Tata Aeris CNG vs Petrol: Running Cost Comparison
CNG remains significantly cheaper per kilometre than petrol in most Indian cities, which is the primary reason buyers choose the CNG variant despite its slightly higher upfront price and marginally lower power output. With CNG typically priced well below petrol per kilogram in most metro markets, and the Aeris CNG returning upwards of 26 km/kg, the per-kilometre running cost works out to roughly half of what the petrol variant costs to run, making it an attractive choice for high-mileage owners such as daily office commuters, cab operators, and delivery fleet buyers.
How Tata Aeris CNG Mileage Compares to Rivals
The Tata Aeris CNG competes primarily against the Maruti Suzuki Dzire CNG and Hyundai Aura CNG in the compact sedan segment. The Dzire currently leads the segment on ARAI-certified petrol mileage, but CNG mileage across this class of cars tends to sit in a similar 26 to 28 km/kg band, since all rivals use similarly sized 1.2-litre engines with twin-cylinder CNG kits. Buyers cross-shopping this segment should compare official ARAI figures at the time of purchase, since manufacturers periodically update certified numbers with running production changes.
Tips to Maximise CNG Mileage on the Tata Aeris
Getting close to the ARAI-claimed figure in daily use depends heavily on driving habits and maintenance. A few practical steps that help:
Maintain steady throttle inputs and avoid harsh acceleration, since CNG engines are more sensitive to aggressive driving than petrol engines.
Keep tyres inflated to the recommended pressure, as under-inflated tyres increase rolling resistance and reduce mileage on any fuel type.
Get the CNG kit serviced at recommended intervals, since a poorly tuned CNG system can silently hurt both mileage and performance.
Avoid running the tank close to empty repeatedly, as very low CNG pressure can affect combustion efficiency.
Use the AMT variant if mileage is the top priority, since it is officially rated higher than the manual gearbox.
Frequently Asked Questions
What is the ARAI mileage of the Tata Aeris CNG? The Tata Aeris CNG has an ARAI-certified mileage of 26.49 km/kg with the manual gearbox and 28.06 km/kg with the AMT automatic gearbox.
What is the CNG tank capacity of the Tata Aeris? The Tata Aeris CNG has a 70-litre water-capacity CNG tank using Tata’s twin-cylinder technology.
Does the Tata Aeris CNG come with an automatic gearbox? Yes, the Aeris CNG is offered with both a 5-speed manual gearbox and a 5-speed AMT automatic gearbox, a segment-relevant feature since not all rivals offer a CNG-AMT combination.
Is the Tata Aeris CNG mileage better than the Tata Tigor CNG? The Aeris CNG carries over the same 1.2-litre engine and CNG hardware as the outgoing Tigor, so its certified mileage figures are in the same range as the Tigor CNG.
What is the real-world mileage of the Tata Aeris CNG? Real-world mileage typically runs a bit lower than the ARAI figure, with most owners likely to see approximately 20 to 23 km/kg in city driving and approximately 24 to 27 km/kg on the highway, depending on driving style and traffic conditions.
When was the Tata Aeris launched and what is its price? The Tata Aeris was launched in India on September 25, 2026, at an introductory ex-showroom price of Rs 5.29 lakh for the base petrol-manual variant, with CNG variants priced roughly Rs 1 lakh above the corresponding petrol trim.
