That is according to a Forbes Aviator blog post by Matthew Stibbe, who gave the London travel hub two places in his list of eight.
The British Airlines Concorde Room in Terminal 5 made the shortlist, competing against eight other airport lounges it offers at Heathrow Airport.
First-class and long-haul passengers can use this facility to dine in private booths, or to take advantage of cabana rooms with day beds and en-suite bathrooms, he noted.
Meanwhile, the Virgin Atlantic Clubhouse airport lounge includes a Cowshed spa offering a sauna, hydra spa pool, facials, massages and haircuts.
"The lounge also features a playground and video games for children and billiards, office space and a library for adults," Mr Stibbe noted.
Virgin Atlantic offers a wealth of flights from Heathrow Airport including to Accra, Miami, New York, Mumbai, Sydney and Shanghai.