TPD insurance premiums are calculated based on multiple risk factors. Age is the primary factor - premiums increase as you get older because disability risk rises with age. Your occupation is crucial, with office workers paying less than manual laborers or high-risk jobs like construction or mining. Gender affects pricing, as women statistically claim more often on TPD insurance. Smoking status significantly impacts premiums, with smokers paying substantially more. Your health conditions and medical history are assessed during underwriting. The coverage amount you select directly affects cost - higher sums insured mean higher premiums. The policy definition matters too - 'Any Occupation' policies are cheaper than 'Own Occupation' because they're harder to claim on. You'll also choose between stepped premiums (which increase each year with age) or level premiums (which remain more stable but start higher initially). Inside super, premiums may be subsidized through tax deductions the fund claims. You can often reduce premiums by accepting a longer waiting period before you can claim.