Travellers booking holidays online are being warned about a scam targeting TripAdvisor users through FlipKey.

The travel website’s FlipKey service has seen scammers pose as legitimate property owners, emailing travellers who show interest in a holiday rental.

Scammers will use FlipKey, which acts as a matchmaker tool for listed holiday rental owners and holiday makers, to secure payments before sending out a fake contract of booking.

According to FlipKey, the responsibility is not theirs as the scam happens through hacking of the owners' email account.

Nina Dela Cruz from Sydney is one of many Australians hit by the scam, losing almost AUD$2000 on a bogus Bali villa.

Ms Dela Cruz said everything sounded great so she transferred the money to “the owner’s” UK bank account.

“I’m a smart person, I’m really careful with all this sort of stuff and because you’re dealing directly with the owner it’s kind of normal that they’d give you their personal account details,” Ms Dela Cruz said.

After the booking was completed she received an email from FlipKey warning her she may have been scammed and contacted the property’s real owner only to find he had never heard of her.

FlipKey chief operating officer Jeremiah Gall said it was not the FlipKey account that was compromised but the property owner's personal email account.