Millions of motorists could be fined each year as Dartford Crossing removes the toll booths this weekend, forcing drivers to pay online, by phone, in shops or by post.
The Dart Charge scheme will begin at 6am on Sunday and operate similarly to London's congestion charge.
Charges for using the M25 toll road will rise by 25 per cent for the new system, with fees set at £2.50 per car and £3 to £6 for HGVs depending on their size. Those living and working nearby will be benefit from reduced rates.
AA President Edmund King told the Daily Mail: "The removal of the toll barriers is welcome but frankly they should be removing the toll charge. There should be no demand management tolls on the M25 as the bridge was paid for a decade ago.
"Many occasional users are likely to be hit with £70 penalties for not paying in time as they don't know about the changes. Drivers must be given a chance to get used to this new system but it really is a toll too far."
Meanwhile, Kent Online reports that charges were temporarily suspended at the Dartford Crossing on Saturday morning because the removal of the payment booths caused traffic chaos.
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