A survey by the Association of District Councils reveals that plans to change the de minimis rules to a stock-based figure of 4,000 properties from July 1998, falling to 2,500 a year later, will hit small authorities hard.
The ADC says there are currently 63 English authorities with more than 4,000 units and a further 42 with stock between 2,500 and 4,000 properties.
The survey found the average cost of preparation for CCT was almost£400,000 per authority, with the highest at more than£750,000.
Many councils fear that the new rules, due to be laid before Parliament along with the rest of environment minister Sir Paul Beresford's new white-collar CCT regulations at the end of the month, will force them to put uneconomic packages of work out to tender.
ADC principal housing officer Jeanette York has written to the DoE's top CCT civil servant, Richard Footitt, detailing the results of the survey.