People objecting to a planned toll increase from 30p to 50p on the Clifton Suspension Bridge have until Friday to voice their opinion.
The suspension bridge in Bristol is run by an independent charity
In October, Tim Baines, clerk to the trustees of the Bristol bridge, said it was run by a charity and received no money from the government.
Objectors needed to write to the Department of Transport by 2 December.
"Everything comes from the tolls and it is important to preserve the bridge for Bristolians," said Mr Baines.
But John McGoldrick, of the National Alliance Against Tolls, said: "The government collects about £1bn every week from roads users.
"There is no justification for tolls on any road including the Clifton Suspension Bridge.
"In the particular case of the bridge there appear to be large financial reserves, and the existing tolls seem to be adequate to meet essential maintenance costs."
About four million motorists cross the bridge a year. The toll rose by 10p to 30p in 2003.