"The estimated cost of drug testing TANF applicants and recipients varies by State and proposed law, depending on the proposed number of individuals who would be tested and the range of activities for which costs were estimated. Aggregate cost estimates of proposed welfare drug testing legislation were identified for twelve States (see Appendix C for details). The estimated costs in these States ranged from $92,487, for drug testing 20% of recipients and treating 2% of those tested in Louisiana, to $20 million, for just the testing of all public assistance applicants and recipients in New York. Other estimates include the cost of increasing staff to monitor or administer the tests, as in Maryland and
Missouri. Idaho’s estimate includes the cost of making programming changes to the State’s information system. Florida’s law and Alabama’s proposal require the applicant or recipient to pay for the up?front costs of the drug test, though both would reimburse those who test negative. Most estimates do not incorporate costs relating to increased substance abuse treatment utilization or to increased child welfare interventions."

Source

"Drug Testing Welfare Recipients: Recent Proposals and Continuing Controversies," Office of the Assistant Secretary for Planning and Evaluation (Washington, DC: October 2011), pp. 6-7.
http://aspe.hhs.gov/hsp/11/Dr…