Steam railways in the South East have warned they face financial ruin due to changes in safety regulations.
The region's heritage lines are funding by trusts or charities
Until now government inspectors have carried out free checks on heritage lines but that is set to stop.
The Health and Safety Executive has decided it needs to free up its inspectors to focus on riskier parts of the railway network.
But the six heritage lines in the region said the safety checks would cost thousands of pounds to carry out.
"The railway couldn't operate without a huge volunteer base because the railway is just so expensive to operate we just can't afford to throw money away, which we don't," Graham Baldwin from the Kent and East Sussex Railway said.
The six heritage railways in the South East - Bluebell Railway, East Kent Railway, Kent & East Sussex Railway, Romney Hythe and Dymchurch Railway, Sittingbourne and Kemsley Light Railway, and the Spa Valley Railway, are run by trusts or charities.
Managers said some may not be able to cope with the new financial pressures.