Tax Office Takes Aim at Tradies and Sales Managers Labourers incorrectly claimed travel expenses for driving to work. The Australian Tax Office is targeting the work expenses of 218,000 building and construction workers and sales and marketing managers as June 30 nears. Find out how to keep the tax man on side in tomorrow's Money . Online and in print. A crack team of analysts, known within the ATO known as ""the doctors"," is using sophisticated techniques, including data mining, to identify unusual patterns of claims. The ATO is targeting the tradies because of rising work-expense claims and the high occurrence of incorrect claims in last year's tax returns. The main problem with work-related expenses is taxpayers not separating private expenses from legitimate work-related ones. Claims should be made only when the expenses are incurred to earn income. Graham Whyte, assistant commissioner of client services and assistance at the ATO, said $18 billion of work-related expenses were claimed last financial year. He said the ATO focused on occupations with a pattern of large or rising claims, or on claims that did not fit the pattern of a particular occupation. Written evidence is needed to support claims for work-related deductions of more than $300. Work expenses claimed incorrectly in last year's tax returns included sales managers claiming for mobile phone calls based on the time spent at work rather than on work-related use. As well, labourers incorrectly claimed travel expenses for driving to work. Travel between home and workplace cannot normally be claimed. The travel expense is only deductible if it can be shown that an employer requires a worker to carry bulky equipment in their vehicle as part of their job. Mr Whyte said the ATO was also writing to more than 110,000 rental property owners who had been identified through last year's tax returns to help ensure they fill out their tax returns correctly this year. Expenses that cannot be claimed include those incurred while the owner is occupying the property. Expenses can only be claimed for that portion of the year when the property is rented or available for rent. Fewer people will need to lodge a tax return this year. Those earning less than $18,200 in a financial year may not need to pay income tax. That is because the tax-free threshold has risen to $18,200 this financial year from $6000 last financial year. For those earning more than $18,200, income tax needs only to be paid on earnings above $18,200.