Retailers have mounted legal action against the Government's decision in 2013 that a cash machine built into the front of a shop should have a separate extra rates bill.
This saw bills sent to thousands of retailers in 2014, backdated to the start of the last tax regime in April 2010.
And this month's controversial business rates changes have seen hefty bill hikes for more than 14,000 cash machines for the next five years.
This is costing retailers £39.3 million - or nearly £2,800 a year on average for each ATM, according to figures compiled for the Press Association.
The long-running case has now reached the Upper Tribunal and the Courts Service said a judgment was due "shortly".
If successful, retailers could be given a reprieve on more than £400 million of business rates bills, with a potential rebate of £200 million for the last seven years and wiping out future charges of £205 million for the next five years.
But if the ruling does not go in the sector's favour, there are concerns that small shops and independent petrol forecourts may be forced to close ATMs or start charging for cash withdrawals.
It comes as the sector is already facing crippling rates rises under this month's revaluation.
The figures from rents and rates specialists CVS show the number of cash machines being liable for business rates has surged from 3,140 in 2010 to 14,068 this year.
Mark Rigby, chief executive of CVS, said charging rates on cash machines was "nothing more than a stealth tax".
He said: "With banks continuing to close branches at an alarming rate, access to cash from retail sites is more important than ever before.
"Should the approach of the Government's agency be upheld and cash machines removed from service, villages and communities will be deprived of convenient access to cash local people need and deserve."
Almost one in six - more than 196,000 - current business rates appeals lodged with the Valuation Tribunal Service relate to cash machines, according to a freedom of information request by CVS.
James Lowman, chief executive of the Association of Convenience Stores, said: "Increased business rates and concerns about the level of remuneration for retailers hosting cash machines could lead to retailers having to make difficult decisions about whether they can continue to provide a machine in store.
"We want to see local authorities use the additional funds provided in the Budget for business rates relief to reduce cost burden."