Donating to a worthy cause is something many of us do, but an incident in regional South Australia has prompted authorities to warn people to be careful when handing over their cash. Key points: You can check online whether a charity is properly registered

Doorknockers should have the proper ID including a badge with a photo

Fraudulent collectors may insist on being paid cash, rather than cheques

If you're suspicious, you can raise your concerns with the ACCC

Police say a group of scammers — as young as 12 — allegedly doorknocked homes at Loxton in the Riverland region earlier this month, asking for donations for a skin cancer charity.

What happened in this case?

At least three people donated money between March 9 and 19, but suspicions were raised when a resident asked one of the boys for a receipt and identification, which he couldn't provide.

The resident told the boy to come back the next day and contacted police.

They set up a sting to catch one of the "fundraisers" in the act.

"Police attended the resident's home and they waited together for the youthful fundraiser to arrive, the boy attended as agreed and he collected an envelope from the resident," Senior Constable Kate Dawson told ABC Radio Adelaide.

"But instead of the cash he was expecting in the envelope, it just contained a single word on a piece of paper that read 'busted'."

The 12-year-old was arrested and is now facing a charge of deception.

So, what should you watch out for?

CEO of the Public Fundraising Regulatory Association Peter Hills-Jones said while he had "never heard of anybody quite as young as 12" taking part in a scam, there were three basic steps you could take to ensure you're not getting ripped off.

First, in South Australia charities should be registered with either the State Government or the federal regulator.

Each state has its own laws about how to register a charitable organisation.

And throughout Australia, you can check the Australian Charities and Not-For-Profits Commission (ACNC) to see whether a particular charity is registered.

"The ACNC website has a very simple and easy-to-use online register," Mr Hills-Jones said.

"If you've got any concerns about that particular charity you can just pop the name in there and it will instantly tell you whether or not they are a registered charity."

Mr Hills-Jones hopes the case doesn't deter people from donating to legitimate charities. ( ABC South East SA: Kate Hill )

Second, there are also rules around when they can collect.

While the regulations vary from state to state, in South Australia the Charitable Purposes Act sets out the times of day door-to-door fundraisers can operate.

"On a weekday that will be between 9:00am and 6:00pm, Saturday 9:00am and 5:00pm and Sundays and public holidays will be 11:00am and 5:00pm," Mr Hills-Jones said.

"If anybody's fundraising outside of those hours it's a potential red flag that they're not legitimate."

The third thing to consider is that a charity representative should be wearing a fully-recognisable charity shirt, jacket or bib and an identification badge with a name and a photo.

"That ID badge should be signed from someone from the charity," he said.

What techniques do scammers use?

The ACCC's Scamwatch arm has reported 93 fake charities in Australia in the last month alone, with consumers parting with more than $261,000.

If you're being contacted by a charity through email, or being asked to donate online, a basic thing to consider is whether you have heard of the organisation before.

And some scammers will set up fake websites that closely resemble those of legitimate organisations.

Mr Hills-Jones said noting the tactics they used was also a good tip.

"No public fundraiser should ever put an individual under what we call 'undue pressure' to give," Mr Hills-Jones said.

Being asked to provide cash instead of a cheque, not being given a receipt, and being given no detail on how your personal information would be treated are also red flags.

"When you sign up with any charity, there should be a very clear statement that explains to you in plain English how your data will be used," Mr Hills-Jones said.

How can you raise concerns?

One way is to notify police.

Another is to contact the ACCC via through the 'report a scam' website.

The Scamwatch website also offers advice on steps to take if you suspect you've been ripped off, including contacting your financial institution.

Should you say no to all door-to-door charity collectors?

Mr Hills-Jones said he hoped the incident did not discourage people from donating to legitimate charities, or avoiding becoming fundraisers themselves.

"It's an extremely tough job. We require that all our members pay the minimum wage. There's not currently an award," he said.

"Typically an average face-to-face fundraiser will sign up maybe four or five people on a good day but they could speak to upwards of 150 people per day.