Petrol Diesel Price Today, August 18, 2026: Petrol and diesel prices remained unchanged across major Indian cities on Tuesday, offering some stability to motorists despite volatility in the international crude oil market. Fuel rates continue to vary considerably from one city to another because of differences in state taxes, transportation costs and other local charges.

Oil marketing companies revise and publish petrol and diesel prices every day. The latest rates generally come into effect at 6 AM, making it useful for consumers to check prices before heading to a fuel station.

Petrol remains above ₹100 per litre in several major cities, including Delhi, Mumbai, Kolkata, Chennai, Gurugram, Noida, Bengaluru, Hyderabad and Jaipur.

Petrol and Diesel Prices on August 18, 2026

Here are the latest petrol and diesel rates reported for major cities:

Among the cities listed above, Hyderabad and Thiruvananthapuram continue to have some of the highest petrol prices, while Chandigarh remains comparatively cheaper.

Actual rates can vary slightly depending on the location of the fuel station, so motorists should check the applicable price in their area before refuelling.

Why Are Petrol and Diesel Prices Different Across Cities?

Fuel prices are not determined by the cost of crude oil alone. Several components are added before petrol or diesel reaches consumers.

This is also why two cities can have noticeably different retail fuel prices even on the same day.

1. International Crude Oil Prices

Crude oil is the primary raw material used for producing petrol and diesel. Since India imports a large portion of its crude oil requirement, movements in international oil prices are closely watched.

When global crude becomes expensive, the cost of importing oil increases. A sustained rise in crude prices can therefore create upward pressure on domestic fuel costs.

Conversely, falling international oil prices can reduce some of the cost pressure, although retail prices may not necessarily change by the same amount or immediately.

2. Rupee-Dollar Exchange Rate

The value of the Indian rupee against the US dollar is another important factor.

International crude oil transactions are largely settled in dollars. If the rupee weakens against the dollar, Indian refiners have to spend more rupees to purchase the same quantity of crude oil.

Therefore, even when crude prices remain stable internationally, currency fluctuations can influence India's oil import bill.

3. Central and State Taxes

Taxes account for an important portion of the retail price paid by consumers.

The central government and state governments impose different duties and taxes on fuels. State-level taxation is one of the major reasons petrol and diesel prices differ across India.

This explains why a litre of petrol can cost substantially more in one state than in another despite both cities receiving fuel from the same oil marketing network.

4. Refining and Distribution Costs

Crude oil cannot be directly used as petrol or diesel. It must first be processed at refineries.

Refining involves infrastructure, energy and operational expenses. After refining, fuel must be transported to depots and retail outlets.

Freight, dealer commissions and distribution-related expenses also contribute to the final price consumers pay at the pump.

5. Demand and Supply Conditions

Fuel markets are also influenced by changes in demand and supply.

Higher economic activity, travel demand, agricultural operations and seasonal consumption can increase fuel requirements. On the global level, geopolitical conflicts, production cuts or disruptions to shipping routes can affect crude oil supplies.

Any significant imbalance between demand and supply can influence energy prices.

Why Have Domestic Fuel Prices Remained Relatively Stable?

Retail petrol and diesel prices in India have seen relatively long periods of stability despite frequent fluctuations in global crude oil prices.

Tax adjustments by the central and some state governments in previous years also influenced retail prices. Since then, consumers in many cities have seen fewer day-to-day changes compared with the volatility visible in international crude markets.

However, global crude prices, exchange rates, taxes and other market conditions continue to remain important factors for the domestic fuel market.

How to Check Petrol and Diesel Prices in Your City

Consumers can check daily petrol and diesel prices through the official services provided by oil marketing companies. Fuel stations also display the applicable rates.

SMS-based services can be used where available. Consumers should verify the latest SMS format and number from their respective oil company's official channel before sending a request, as these services may be revised over time.

Since prices can differ between states and even between nearby locations because of local taxes and transportation costs, checking the rate applicable to your own city or fuel station provides the most accurate information.

What Motorists Should Watch Next

International crude oil prices remain an important factor for Indian consumers. Any major change in global supply, geopolitical tensions or the rupee-dollar exchange rate can alter the cost environment for oil marketing companies.

For August 18, 2026, however, petrol and diesel rates remain unchanged in the major cities listed above. Motorists should continue checking daily rates, particularly if global crude oil prices remain volatile in the coming days.

Disclaimer: Fuel prices listed above are based on the rates reported for August 18, 2026. Prices may vary by location and retail outlet. Consumers should verify the latest rate with their local fuel station or oil marketing company.