Costs for small businesses in Australia rose to 124.6 by March 2026 from 100 in March 2020, an almost 25% jump since the COVID-19 pandemic, according to the inaugural AMP Bank GO Small Business Cost Pressure Index on Tuesday.

The index measures the key costs faced by most small businesses to stay open, with the costs weighted to reflect their overall significance.

Since March 2020, insurance jumped 52%, fuel was up 38%, interest costs were up 36%, and electricity rose 26%.

"While inflation has come down from its peak, many small business costs remain high," AMP Deputy Chief Economist Diana Mousina said.