Need to know
Sixty, including 10 suites.
Noon, but possibly later, if availability permits. Check-in, 3pm.
Double rooms from $261.11 (£203), excluding tax at 20 per cent. Please note the hotel charges an additional service charge of 5% per room per night on check-out.
Rates exclude breakfast (£16 for Continental).
Don’t miss the hotel’s cocktail hour, not just for the delicious concoctions on offer in the bar, but also for the ever-changing popcorn flavour of the day. Try to catch one of the hotel's cheese and wine or chocolate masterclasses. Sommelier Christophe Thuilot has extremely trustworthy tastebuds and his unconventional pairings (soft Tunworth cheese with cider) give a new twist to the classic cheese board. Or indulge yourself by barely leaving your bed: the hotel's teamed up with Perfect 10 Black Label, to offer guests a pampering menu of spa and beauty treatments. Facials, massages, mani-pedis, reflexology and hair-coiffing are offered alongside luxury wet shaves for resident gents.
At the hotel
In-room spa and beauty treatments, free WiFi throughout, valet parking (£59 a day). In rooms: flatscreen TV, VDA multimedia system with music and videos, iPod dock, minibar, free bottled water, Hypnos beds, Penhaligon's bath products.
Our favourite rooms
The huge sixth-floor Terrace Suite is the ultimate London crashpad: vast, with an open fireplace and a large terrace overlooking surrounding St James. Even more decadence-drippingly exclusive, the St James and Westminster Suites (which can combine to create the Penthouse) are accessed via their own private lift. More modest – but still featuring the same sumptuous silk wallpapers, polished stone bathrooms and hi-tech gadgetry – are the Executive Rooms – ask for one with a Jacuzzi or a balcony.
Mr Smith should definitely bring an extra bag (or money to buy one) – the gentlemen’s tailoring options in Mayfair are unparalleled in London.
The hotel has an impressive stash of 20th-century portraiture, including the 1920s–50s Rosenstein Collection, which adorns its public spaces and suites.
Cots (£36 a night) and extra beds (£60 a night) can be added to rooms. There’s a kids’ menu, and babysitting can be arranged (minimum four hours) with three days' notice. The kids’ concierge can arrange attraction tickets, day trips and early high teas.