Background: This study assesses the long-term cost-effectiveness of this screening protocol from a healthcare system perspective. Methods: Australians presenting to private oral healthcare practices recruited to the iDENTify study were included as the study population. A Markov model preceded by a decision tree was developed to assess the intervention’s long-term cost-effectiveness when rolled out to all eligible Australians, and measured against ‘no-intervention’ current practice. The model consisted of four health states: normoglycaemia; pre-diabetes; type 2 diabetes and death. Intervention reach of various levels (10%, 20%, 30%, and 40%) were assessed. The model adopted a 30-year lifetime horizon and a 2020 reference year. Costs and benefits were discounted at 5% per annum. Results: If the intervention reached a minimum of 10% of the target population, over the lifetime time horizon, each screened participant would incur a cost of $38,462 and a gain of 10.564 QALYs, compared to $38,469 and 10.561 QALYs for each participant under current practice. Screening was associated with lower costs and higher benefits (a saving of $8 per person and 0.003 QALYs gained), compared to current standard practice without such screening. Between 8 and 34 type 2 diabetes cases would be avoided per 10,000 patients screened if the intervention were taken up by 10% to 40% of private oral healthcare practices. Sensitivity analyses showed consistent results. Conclusions: Implementing type 2 diabetes screening in the private oral healthcare setting using a simple risk assessment tool was demonstrated to be cost-saving. The wider adoption of such screening is recommended.