September arrives with more pressure on the wallets of Spanish households. The leading indicator of the Consumer Price Index (CPI) published by the National Institute of Statistics places the inflation for August at 4.3% year-on-year, seven tenths above the 3.6% recorded in July.
It is the highest level since February 2023 and represents a considerable acceleration compared to the beginning of summer. Spain thus enters the new term with three particularly sensitive areas: fuels, the electricity bill, and food.
The data is still preliminary and must be confirmed by the INE in September. The underlying inflation, which excludes energy and unprocessed food from the calculation due to their higher volatility, offers a somewhat less negative picture: it decreases by one tenth and stands at 2.9%.
Gasoline and diesel drive up the CPI
The main reason for the jump in August lies in the service stations. The INE explains that fuels and lubricants for personal vehicles have increased this year, while in August 2025 they had decreased, causing a strong effect on the year-on-year comparison.
The escalation has intensified throughout the summer. Since its beginning, gasoline has become around 20% more expensive and diesel nearly 24%, reaching average prices close to 1.72 euros per liter for gasoline and 1.86 euros for diesel.
The conflict in the Middle East and the difficulties for international oil supply are behind much of these tensions. The result comes just as many households face in September the return to work and school, with a usual increase in daily commutes.
The Government has already planned to strengthen measures to contain the price of diesel during September. The subsidy planned for this fuel will rise to 20 cents per liter, after its increase activated the mechanism included in the anti-crisis shield.
The electricity bill remains under pressure
The second threat is electricity. August has been marked by high prices in the electricity market, driven by increased consumption during heat waves and by the rising cost of gas used in combined cycle plants.
The receipt of an average consumer covered by the Voluntary Price for the Small Consumer (PVPC) pointed during August to an increase of more than 20% compared to the same month in 2025, according to calculations made on the evolution of the market.
The energy situation has also forced the Executive to maintain fiscal protection mechanisms. The royal decree approved in June establishes that, if certain levels of year-on-year price increases are met, the VAT on electricity during September will be 10% for supplies with a contracted power of up to 10 kW and for certain vulnerable consumers covered by the social bonus.
The same mechanism includes a Special Tax on Electricity of 0.5% in September if the conditions set by the regulation are met.
The problem is that any prolongation of the increase in energy prices has an impact that goes beyond the domestic bill itself: it raises the costs of transportation, industry, agriculture, and distribution and may end up being passed on to other products.
Food is a concern again
Food is precisely the third element that households are monitoring as autumn approaches. The advance of the CPI indicates that food and non-alcoholic beverages also contributed to the increase in inflation in August, due to their prices falling less than in the same month of the previous year.
Fresh products also show signs of greater tension. Their inflation would have reached approximately 4.5% in August, in a context where farmers, ranchers, transporters, and manufacturers bear higher costs related to fuels and energy.
This transmission is not automatic or immediate, but persistently high energy prices can ultimately affect the final price of the products that reach the supermarket.
The beginning of September also adds significant seasonal expenses for many families: school supplies, books, clothing, transportation, and the recovery of daily commutes after the holidays.
Spain enters September with an inflation rate of 4.3%
The figure of 4.3% corresponds to the advance of inflation in August, not to the inflation of September, which will not be known until the end of next month. However, it is the data with which Spain enters September and serves as a reference to measure the recent deterioration of the cost of living.
In just a month, the rate has gone from 3.6% to 4.3%. And if the Harmonized Consumer Price Index is used, which allows for comparisons with the rest of Europe, Spanish inflation even rises to 4.5%.
The evolution of the coming months will largely depend on what happens with energy. If fuels moderate their rise and fiscal measures reduce part of the impact on electricity and gas, the pressure could ease. If energy costs remain high, the risk is that the increase will extend to more goods and services and end up feeding underlying inflation again.
For now, September begins with a clear warning for households: filling the tank, turning on certain electrical appliances, and grocery shopping are already more expensive than a year ago, and autumn arrives with few guarantees that the pressure will disappear in the short term.