Protests have been held at five train stations across Kent ahead of an expected announcement of higher ticket prices.
Figures out today reveal July's inflation has been set at 3.1%.
Train firms are allowed to increase rail fares by an average of July's inflation rate plus 1%.
The increases will be brought in from January 2014, meaning that, nationally since 2008, fares have risen three times faster than average earnings.
Campaigners have been at Rainham, Chatham, Tonbridge, Ashford and Canterbury West Stations this morning.
One passenger, postman Paul Cox, 51, from Chatham, said: "It's disgraceful at a time when we're apparently all in it together and wages are going down as was reported this week.
"I don't drive personally so that's out of the equation. Unfortunately I'm pretty much tied in to the trains. I think there's a lot of people in that position, we're handcuffed."
Medway Labour group leader Vince Maple admitted his party's even higher increases when in government - of RPI plus 3% - were wrong.
He said: "I think in the time we've been in opposition there's been a recognition that RPI plus 3% was a step too far, and of course the other thing to remember is the financial times we find ourselves in are very different now."
But he added: "Passengers are already here in Medway paying the best part of nearly £5,000. They're quite likely to see a 4% increase in fares from next January and quite frankly that's 4% that no one can afford.
"I think it's about recognising that these are difficult times. As they do like to say repeatedly we are all in this together, so actually to see a reduction in the level that fares increase at this time, if you had inflation minus 0.5%, that would actually mean a bit of a difference to hard-working people who are commuting.
"Lots of people's London weighting doesn't even come close to covering the rail fares."
Mike Hewitson, of campaign group Passenger Focus, said people will feel cheated.
He added: "Its the inflation-plus element that gets to the heart of commuters, particularly as they don't feel they are getting value for money now.
"You can almost begrudgingly go with inflation increases, it's when it's above inflation - particularly in today's economy and climate - that's when it really starts to hurt."
A spokesman for the Association of Train Operating Companies said today: “Government determines how the average season ticket price rise is set each year.
"Since 2004, it has been Government policy to allow regulated fares to rise above inflation in order to support investment in more trains, better stations and faster services.
“This is helping to drive passenger satisfaction to near record levels while seeking to reduce taxpayers’ contribution towards the cost of running the railways.
“In order to help limit future fare rises, the rail industry is working with the Government to find ways of providing services even more efficiently, building on the progress that has already been made.”