John Saunders had to sell a strip of land in Maesycymmer under a compulsory purchase order (CPO) for construction of the A469 relief road in 1991.
He has been paid £280,000 so far but his total payout is yet to be agreed.
A high court judge has now ordered that his compensation claim be considered by a tribunal.
Mr Saunders, owner of Tyn Y Coed Farm, was forced to sell the land used in the development of the A469 Lower Rhymney Valley Relief Road.
Judge Milwyn Jarman QC, sitting in London on Friday, said Mr Saunders received an advance payment of more than £190,000 plus interest in connection with the Caerphilly Council CPO in 1997.
But a quarter of a century after the sale, his final settlement is yet to be confirmed.
The construction of the road severed the main access to the west of his farmhouse and farm buildings, via an underpass. It also cut the drainage system from the farmhouse.
Judge Jarman upheld an application by Mr Saunders and ordered Caerphilly to refer his case to the Lands Chamber of the Upper Tribunal for calculation of the total amount he is due.
A Caerphilly farm owner who was forced to sell land to make way for a relief road may be fully compensated after a 24-year wait.