Banner-waving pensioners demonstrated outside Devon County Council's headquarters on Tuesday at a 5.25% council tax increase.
Protestors at Devon County Hall said the increase was too high
About 40 people joined the protest outside Devon County Hall in Exeter, where councillors confirmed the rise in the authority's council tax from 1 April.
Members of the Devon Pensioners Action Forum lobbied councillors as they arrived for the meeting.
The forum launched its campaign against council tax rises last year when the
authority set tax nearly 18% higher.
Forum chairman Albert Venison, 78, said: "This increase is much too high.
"There is no way that we can afford to pay the 18% from last year so any increase this year is a waste of time.
"This is causing a great deal of hardship. Every time you want to spend any money you have to think about whether you can afford it or not because council tax is depreciating your income all the time."
A group of the demonstrators packed into County Hall's public gallery to watch the councillors' debate.
A petition with more than 3,000 names from people in opposition to cuts in social services was also handed to the council.
Mr Venison said he believed the meeting was a rubber-stamping exercise and walked out in protest.
Council leader Brian Greenslade said: "We have sympathy with the protesters because Devon County Council has been calling for the same thing as them - that the council tax system needs to be radically changed.
Devon County Council approved a 5.25% council tax increase
"I think these people have acquitted themselves very well in how they came here and made their point."
However, the council's deputy leader, Christine Channon, was critical of the pensioners for their actions and what she called an attempt to "frustrate democracy".
She said: "I think it does a real disservice to pensioners who have written to me, whose letters I have replied to and to whom I have tried to explain that I was sorry they were really angry about this.
"But rent-a-mob and civil disobedience I don't believe get anywhere."
Despite the increase, cuts of £11m will still be made to balance the budget. This will hit education support, road maintenance and cut more than £3m from social services.
County councillors in Cornwall have thrown out plans to increase local taxes by 9%.
At a meeting on Tuesday, it was decided that the executive would reconsider a budget looking at an increase of 6.9%, which would add an extra £1 a week to council tax bills.