Fares to rise by average of 2.8% next year, but some commuters face above-inflation increases while wages lag behind

Train fares in England will rise by an average of 2.8% next year, the smallest such increase for four years, a rail industry group has announced. However, consumer groups said this was more than the average wage growth of around 0.7%, and masked some above-inflation increases.

The rises will take effect on 2 January. The announcement was delayed after the chancellor, George Osborne, decided this month that regulated fares – about half of the total, taking in mainly season tickets and open or peak-time fares – would be restricted to an average increase matching the retail price index (RPI) inflation figure, rather than the previously agreed RPI plus 1%. The RPI figure is taken from July, when it was 3.1%.

Individual regulated fares can rise by 2% more than inflation – less than the previous maximum of RPI plus 5% under the "flex" rule – and there is no cap on rises to unregulated fares, mainly connected to off-peak travel.

The Rail Delivery Group (RDG), the industry body comprising rail operators and Network Rail, said the overall fare rise would be 2.8%. It said rail firms strongly supported the government's decision to cap fare rises.

Michael Roberts, the director general of the RDG, said: "Nobody likes paying more to travel by train, particularly to go to work, but billions are being spent to serve passengers better. While major projects like the new King's Cross or Birmingham New Street stations are plain for all to see, work has also been proceeding with thousands of smaller, less visible schemes to improve tracks, signals and tunnels. Investment in new trains has improved passenger comfort and helped make possible 4,000 more services a day than in the mid-1990s."

A number of fares will rise by more than the inflation rate, which is itself considerably above the average wage rise of around 0.7%. The price of an annual season ticket for travel between Cambridge and Peterborough, for example, will rise by 4.07%.

Given the cost of season tickets, even some below-inflation rises have a significant net effect: the annual fares of London commuters from Dover Priory and Deal, in Kent, will edge above £5,000 with an increase of 2.93%.

The Campaign for Better Transport, which lobbies for affordable travel, said the increases were too high. The group's chief executive, Stephen Joseph, said: "Passengers will see season tickets going up three times faster than their wages. The government needs to do more to stop the squeeze on commuters and avoid pricing people off the railways. We need a permanent end to inflation-busting fare rises calculated using an out-of-date formula."

Joseph said increases should no longer be calculated using the RPI but should instead be based on the Consumer Price Index, now used by government statisticians as the main measure of inflation. This tends to run slightly lower than RPI, and in July was 2.8%.

He said: "The government has already switched to CPI for most things. Doing the same for train fares would have little impact on railway revenues but it would save passengers money and bring fares into line with things like public sector pensions."

The shadow transport secretary, Mary Creagh, said it was "completely unacceptable" for passengers to learn about 2014 rail fare rises two days before Christmas. "People deserve timely information to budget effectively. Rail fares have risen 20% under this government. David Cameron is doing nothing to tackle the cost-of-living crisis. Labour would remove the flex and put a tough cap on rail fares."

A Department for Transport spokeswoman said ministers understood the pressures on household budgets, which was why regulated fares were limited to an inflation-only rise. She said: "As well as protecting regulated fares, the government is driving forward the biggest programme of rail modernisation programmes ever, with £38bn being invested over the next five years. That means new state-of-the-art trains, better stations and hundreds of miles of electrified track which will help cut journey times, provide better connections and stimulate growth across the country."

Most fares will change on 2 January, but the price of journeys taken within London will increase on 19 January to coincide with changes to Transport for London fares.