State and Federal Governments are facing growing backlash from HomeBuilder applicants who say they have missed out on a grant of up to $25,000 because of "glitches" or technical issues with the online application process.

Clint Calman, from Southport, Queensland, bought his $599,000 townhouse off the plan from developers on December 23 last year.

The added incentive of a $25,000 HomeBuilder grant was one of the main reasons he decided to build a new home, he says.

"It was a mad rush at the time because if you hadn't executed your contract by the 31st of December the grant would drop down from $25,000 to $15,000 - so everyone wanted to get it done in time," Mr Calman told nine.com.au.