Craig Nickels, 30, and fiancee Ellie Austin, 24, were forced to hand over $470 (£350) for a four-mile journey after getting into an unlicensed cab.
The couple from Derby handed over the cash as they were scared of being attacked, or of having the wedding ring he had brought to propose with stolen.
Cops in New York are searching for the two men who conned the couple just moments after they had arrived at JFK Airport.
Craig, a Tesco worker, said he should have been suspicious before even getting into the cab.
“Obviously it was a brilliant holiday, but the scam did take the shine off it”
A man standing outside the airport offered them a cab to their hotel, and Craig assumed it would be on a meter.
But the man led them away to a private car park and into a minibus driven by a second man.
He then asked them for a $20 (£15) parking fee — which the tired couple assumed would be taken off the bill.
The driver said they would sort the fare “when we get there,” before asking for Craig’s passport details, address and date of birth.
“He started explaining to us there were new toll fees for going between boroughs and over bridges,” said Craig.
“He then told me to take me to Manhattan it was going to be $900 (£674).”
The dad-of-two said: “I knew it was supposed to be $50 or $60 but I started to get scared.
“There were two guys and I had no idea what they were going to do.
“I was worried they’d drive off with the bags, or they had a weapon.”
He went on: “Me and the Mrs couldn’t believe what we were hearing. We only had $900 total”.
Craig said the cabbie was “going on and on about how his boss would get involved, and while he wasn’t physically forceful, he was trying to scare me”.
Eventually, the driver said he would “drop” the fare to $470 (£350) at which point Craig gave in and handed over the money.
When they explained the situation to subway staff, they were given a ticket to Manhattan for free.
Craig and Ellie, who saved up for months for the holiday, gave statements to police when they returned to JFK five days later.
Police said they had heard of the scam artists before, and they had heard of them driving off with people’s luggage before.
Police told them they weren’t going to get their money back.
Craig’s parents sent the couple £400 for the rest of the holiday, and he went on to propose to Ellie at the top of the Rockefeller Center.
“Obviously it was a brilliant holiday, but the scam did take the shine off it,” Craig said.
Police have warned tourists to stick to official yellow cabs in New York.