If you are a small business or contractor and you're still waiting to be paid for work you completed months ago — you're not alone.

Key points: Push for Government to force big businesses to pay small business suppliers within 30 days

Push for Government to force big businesses to pay small business suppliers within 30 days 60 per cent of 3,000 submissions from small businesses said it was getting worse

60 per cent of 3,000 submissions from small businesses said it was getting worse Recommended companies should publicly report their performances

Big businesses and multinationals have effectively been using smaller businesses as a cheap form of finance by dragging their heels on payments, according to the Federal Small Business Ombudsman.

And now Kate Carnell is urging the Federal Government to put laws in place to force big businesses to pay small business suppliers within 30 days.

She also wants governments to lead by example by setting an even tighter deadline of 15 days.

Ms Carnell and her office conducted an investigation into slow paying, looking at 3,000 submissions from small businesses.

Sixty per cent of those businesses said they thought slow payments were getting worse.

"[It] is huge number, and we've found it's pretty widespread," she said.

"Large, billion-dollar multinational companies are extending their payment times to as long as four months — no small business can last that long.

"So they are fundamentally using small-to-medium Australian businesses as cheap banks."

When the Harvard Business school reviewed the US government's move to a 15-day deadline for payments, they found it created 75,000 jobs and delivered $6 billion to workers' payroll in the US.

"So there's real evidence to show that it produces jobs and growth," Ms Carnell said.

Cash flow 'the fuel of our economy'

Ms Carnell said while she was calling for the Australian Government to follow the US example by introducing 15-day deadlines, 30 days was a more realistic figure for private businesses.

But if a business needed a longer term and it was found appropriate, they could negotiate the time frame.

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"As long as it's not unfair to one party — but if there's a dispute on that contract, then a longer term could be deemed to be an unfair contract clause," Ms Carnell said.

"So there doesn't need to be the contract police."

She explained that those disputes would be mediated in the court system, "or alternatively, places like my office".

"[My office] handles business-to-business disputes, so there's a number of ways it can be done," she said.

"But fundamentally we've got to put a line in the sand — if large, multinational, billion-dollar companies can continue to push out their payment times for small business, it stops the economy growing.

"Small businesses can't invest in their businesses, they can't employ if they don't have cash flow.

"Cash flow is the fuel of the engine room in our economy, so we've got to get cash flow moving for small business."

'We need to name and shame'

Ms Carnell also recommended companies should have to publicly report their performances.

"We think that naming and shaming is a good idea," she said.

"And you can't do that unless we've got actual publication of what's happening with payment terms and times — they've done this in the UK.

"We're talking about the top 100 companies in Australia being required to report twice a year on their payment times, their terms and how they've delivered against those.

"We will be starting the process of setting up a national transparency register website to encourage this to happen."

Ms Carnell said she would be disappointed if the Government were to not take the recommendations seriously.

"The Government, and for that matter the Opposition and all parts of Parliament, continue to talk about the small business sector as being the engine room of the economy," she said.

"For the engine room to work properly we've got to have cash flow."