Vale Council says it's facing a budget shortfall of £14.8 million for the next financial year.
Council leader Lis Burnett says the authority is still facing an "extremely challenging" financial position as it looks towards setting its annual budget.
A report, set to be discussed by cabinet members this week, says growing demand for social care and provision for school pupils with additional learning needs, is still having a key impact on its books.
Next month, the Welsh Government will announce how much the council will get as part of its annual funding settlement.
Cllr Burnett said: "There is no disguising the fact the council remains in an extremely challenging financial position."
“Local authorities have seen consistent real terms funding cuts for more than a decade and when combined with rising costs, it is becoming harder and harder to balance the books."
“The obstacles facing us are huge, but the council has an ambitious transformation agenda that we are confident will bring efficiency savings across the organisation, while careful use of reserve funds can also help address the problem."
"Even so, this is an extremely testing situation, one that will mean further difficult and unpalatable decisions lie ahead as we look to protect the services relied upon by our most vulnerable residents."
According to the report, Vale Council is facing cost pressures of around £34.3 million - with estimates suggesting that funding will only cover around £7.8 million, leaving a shortfall of £25.9 million.
But the council says it's carried out a thorough review to give it a "realistic target" for its transformation and savings programme to bridge the gap.
As such, the headline pressures have been reduced to £23.2 million, giving a residual budget gap of £14.8 million.
While high energy prices, inflation and interest rates have played a part in compounding dwindling resources, the biggest cost pressures facing the council come from the growing number of ALN school pupils and people requiring social care.
Schools and social care are set to account for 70 per cent of the council's budget in 2024-25 - a figure which is likely to increase further in the future.
A spokesperson for Vale Council added: "That emphasises the fact that, even with a reshaping programme to redesign how council functions operate, services in other areas cannot be sustained at current levels."
A number of working groups are looking at where potential savings could be made before proposals are presented to the council's cabinet - with final decisions set to be made in March.
Last month, Chancellor Rachel Reeves set out an additional £1.7 billion for the Welsh Government as part of her first Budget.
But that includes the next two financial years - with resources covering annual pay rises and a significant share likely to go towards the health service in Wales.
Local government's share of the funding will be known when Finance Secretary, Mark Drakeford, sets out the Welsh budget on December 10th.

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