He’s a cabby with a conscience.

A man who may be the most honest hack in town went out of his way to return a brand-new iPhone 5 to an absent-minded fare — and refused to take a dime in reward.

“Money is nothing to me,” Mohammad Riyaz said after returning the pricey phone to an IBM sales manager who had left it behind after hailing a cab from Madison Square Park to his Upper West Side brownstone.

“This is what it is all about,” Riyaz said about helping others while parked outside the unidentified fare’s home on West 69th Street.

Riyaz spotted the latest iPhone — which can cost from $650 to $850 and is a prized target for thieves — and doggedly tracked down its businessman owner.

The sales manager’s wife, who gave her name only as Marie, said she and her grateful husband tried to persuade the selfless Riyaz to accept $80 cash as a reward and to pay for his trip back uptown.

“What can I do to get you to take it?” she told Riyaz. “And the guy wouldn’t take the money.”

“We tried so many times and he was so nice, so so nice,” added her hubby, who asked not to be identified.

Riyaz said the good deed was all the reward he needed.

“If I died today what’s my money going to do?” he asked. “If I do something good now then when I die good things will happen in the next life.”

Riyaz insists he routinely returns lost “cellphones, iPads and sometimes luggage” to forgetful owners.

For the 30-year-old bachelor, a native of Bangladesh, helping others is priceless.

“It was more than enough to give the person what was theirs,” he said.

The cabbie’s charitable act drew praise from the city’s Taxi and Limousine Commissioner.

“Well done, Mr. Riyaz! As so many taxi drivers do, he exemplifies the professionals who made New York’s taxi industry the finest in the world,” Commissioner David Yassky said.