Software that three police forces hoped would make them more efficient could be scrapped before it is rolled out.
Thames Valley, Sussex and Surrey Police said they have paid £3.3m in total to accountancy firm KPMG since 2016 for the new program, Equip.
The Thames Valley's Police and Crime Commissioner (PCC) said the forces' internal costs were "very considerable" and exceeded the total paid to KPMG.
Their chief constables may recommend the project is ditched within weeks.
Thames Valley's PCC Anthony Stansfeld said he was "totally dissatisfied" with Equip's progress.
A joint implementation team working across the three forces has 47 staff.
The software would be used for financial management, human resources and recruitment and the forces say it would save them "valuable time and money".
The Thames Valley Police Authority's annual accounts for 2019-20 state the forces' total commitment to KPMG is £9.4m.
But draft accounts on the website of David Munro, Surrey's PCC, state his force alone had incurred total costs of £5.7m - including charges paid to KPMG - by the end of 2019-20.
Sussex Police said it had paid a total of £2.4m in charges to KPMG and internal costs involved with the project by the end of 2019-20. Thames Valley Police said £4.3m was outstanding on its share of the capital contract.
Thames Valley Police's chief constable John Campbell said the system was "complex" and "not delivering what we want it to".
The chief constables will recommend whether the software should be scrapped or whether work on it should continue.
The draft accounts for 2019-20 of Sussex's Police and Crime Commissioner, Katy Bourne, states the force was "currently undertaking detailed work to review and re-plan the programme to determine the new implementation date and project costs".
KPMG has been approached for comment.