The leader of the Durham County Council's Independent group said he had been taken aback by North Yorkshire County Council's belief that removing unnecessary waste and duplication would achieve vast savings for a unitary authority.
Councillor John Shuttleworth said since a single council had been created from eight authorities in County Durham in 2009, potential savings had been negated by pay rises for senior officers.
In 2007, ahead of its reorganisation Durham County Council forecast a unitary system would save £21m a year, a figure it told a North Yorkshire County Council briefing last year it had almost achieved.
Durham Council said significant further savings were made through reorganisation once the new council had bedded in and said its senior management costs had fallen by £2.823m as 52 senior posts were reduced to seven.
Coun Shuttleworth said while Durham saw 24 heads of service roles drop to about 13, the number of heads of service had since returned to about 23.
Two officers who had held leading roles on other authorities were handed 80 per cent pay rises, while Durham council's head of transport and the head of access and inclusion went from £65,000 to £95,000, a 44 per cent pay increase.
The head of education, head of achievement services and head of safeguarding and specialist services saw even greater increases, with their salaries going up by 55 per cent, from £70,000 to £110,000.
Coun Shuttleworth said many officers were awarded "eye-watering pay rises" overnight despite their roles not changing to bring their salaries into line with others at the new authority.
He said: "I haven't seen any savings, but the senior management will say there have been savings because they are looking after themselves."
Leader of the North Yorkshire council, Councillor Carl Les, said people had been right to raise concerns over salaries and those concerns would be listened to. However, he said officers pay would be a question for a new elected interim executive board to consider.
He said pay increases would not match the decrease in costs created by removing eight chief executive posts and replacing them with one, which would remove almost £1m of expense a year.
Coun Les said: "I would say if the job is the same I can't see a reason why you would have any increase other than one related to the cost of living, especially at this time when there has to be caution over the costs that we are going to bear going forward.
"We have had our savings figure verified by PriceWaterhouseCoopers because we didn't want to put figures forward that weren't accurate."