Hotel rooms that really sleep four: London, Paris, Rome and New York

Two queens or two doubles in a standard room is how American hotels are built, so in New York a family of four pays a room rate, not a suite rate. Five of our ten New York hotels sell an ordinary room with two beds: TWA Hotel, 1 Hotel Brooklyn Bridge, The Beekman and Nine Orchard all showed one for our family on Expedia, and The Plaza has its Deluxe Two Queens, though it had no room for us that night.

The cheapest was the TWA Hotel at JFK: $304 with tax for a Deluxe Room with two queens, the room for the night before an early flight or after a late one. In the city, 1 Hotel Brooklyn Bridge's two-double room in Dumbo was $770, The Beekman's two-queen room in the Financial District $838, and Nine Orchard's Dual Queen, the biggest of them at 475 sq ft (44 m²), $1,320. For two bedrooms and two bathrooms, Nine Orchard's Two Bedroom Corner Suite was $1,961.

Outside our edit, the Residence Inn on Broadway in Midtown was $498 for a studio with two doubles and breakfast, and Hotel Beacon on the Upper West Side $728 for a one-bedroom suite with two doubles. The Plaza, Hotel Chelsea and citizenM New York Bowery had no room for four on Expedia that night; citizenM's rooms take two.

Two of our ten London hotels sell a standard room with two double beds, and both are good buys. Sea Containers London's Superior Double Double on the South Bank was the best price in our edit at £409; the hotel calls these rooms perfect for families. The Standard, London's two-double room at King's Cross, a generous 36 m², was £472. For £538, Town Hall Hotel in Bethnal Green sold a two-bedroom suite of 59.8 to 86.6 m², the cheapest room in our London edit with a door between parents and children.

Outside the edit, the Leonardo Royal by Tower Bridge was £363 for a room with two queens, and Citadines Trafalgar Square £424 for a 70 m² two-bedroom apartment with a double in one room, two singles in the other and a kitchenette.

At the top, The Ned's Two Bed Family Suite (95 m², a super king and a queen, two bathrooms) was £1,917 and Claridge's Two Bedroom Mayfair Suite (115 m², two kings or a king and twin beds) £3,341. Hazlitt's, Artist Residence London and The Pilgrm had no room for four that night; The Pilgrm says its rooms are too compact for an extra bed.

Most of Rome's grand hotels sell rooms for two or three. In our edit, only The Inn at the Roman Forum sells one unit for four as a matter of course, and that is an apartment; elsewhere, four means a suite. The best buys were at Palazzo Manfredi, by the Colosseum. Its Marco Aurelio Apartment, 400 metres from the main building, was €534 with a double and a queen as Expedia lists them, and its Family Suite, two bedrooms with a double each and two bathrooms looking over the Colosseum, was €1,840.

Outside the edit, Hotel Raffaello in Monti sold its Family Suite, a king and two singles in two separate areas, for €466: the cheapest real beds for four in Rome that night. Hotel Santa Maria in Trastevere and Hotel Smeraldo near Campo de' Fiori both have family rooms on their own sites, a Quadruple Room with a double and a bunk, and a 60 m² two-bedroom Family Suite, but neither had one on Expedia for that night.

At the top, ROMEO Roma's Fresco Grand Suite, 111 m² with a king in each of two rooms, was €3,638, and Six Senses Rome's Mellini Suite, two king bedrooms and a 30 m² terrace, €8,166. Orient Express La Minerva, Bvlgari Hotel Roma and Donna Camilla Savelli had no room for four that night, Hotel San Anselmo's own booking engine caps every room at two guests, and Expedia could not price Rhinoceros.

None of our ten Paris hotels sells a standard room for four. Seven need a suite and three need two connecting rooms, and Le Bristol caps every room and suite at three guests. The best value in our edit is at Hôtel Molitor in Auteuil, around its famous pool: two connecting rooms with a queen each, sold as one Superior Family Room, for €710, or the Deluxe Family Room with two kings for €796.

In the centre, Le Pavillon de la Reine on the Place des Vosges sold its Family Duplex, 2 Bedrooms, Courtyard Area for €2,323. It matches Le Petit Pavillon on the hotel's own site, a three-level house in the courtyard with its own entrance, two bedrooms and two bathrooms. Mandarin Oriental Lutetia's Family Room, two connecting rooms with a king and two singles and two marble bathrooms, was €3,927.

The value answer sits in the Marais, outside our edit. The People Paris Marais, a hotel and hostel near the Île Saint-Louis, sold a family room with a queen and a bunk for €230, and Hôtel Jeanne d'Arc Le Marais its 30 m² Family Room, a double and two singles, for €433.

Hôtel de Crillon, Le Bristol, Le Pigalle and Grands Boulevards Experimental had no room for our family that night. Le Bristol's Family Spirit offer, two rooms for two adults and two children up to 12 with the second room up to 50% off and a two-night minimum, is on the hotel's own site.

No. "Sleeps 4" on a booking page tells you how many people a room is sold for, not how many beds are in it. Of the 89 room types Expedia sold to our family as sleeping four or more at our hotels, 40 put two of the four on a sofa bed or pull-out, or listed a single bed: 15 of 24 in Paris, 13 of 27 in New York, 7 of 19 in Rome and 5 of 19 in London. Many are lovely rooms, and a good sofa bed is fine for a 6-year-old for a night or two. The point is to know before you book.

Watch the age limits too. The Ned's Stairwell Studio takes two adults and two children only if the children are under 12, and every Shangri-La Paris suite puts two children under 12, or one adult, on the sofa bed. Outside our edit, Hotel Beacon's Double Deluxe has two double beds but takes two adults and one child.

A listing can also undersell a room. Expedia shows one king for ROMEO Roma's Fresco Grand Suite, which has a king in each of two rooms, and one single for Hotel Raffaello's Family Suite, which has a king and two singles. These are the rooms where the hotel's own page tells a different story from "sleeps 4".

Children change the bill in two of the four cities. In Rome the contributo di soggiorno is charged per person per night, for up to ten nights, but children are exempt until their tenth birthday, so a family with children of 9 and 6 pays for the two adults only: €20 a night in a five-star hotel. A 10-year-old pays the full adult rate. In Paris the taxe de séjour is charged per adult and everyone under 18 is exempt, so our family pays €31.86 a night at a Palace such as Shangri-La Paris or Mandarin Oriental Lutetia.

New York charges per room, not per person, so children make no difference: 14.75% plus $3.50 a night, already inside the Expedia totals in our New York table. A suite pays the $2 room charge on each room it is made of, and two connecting rooms pay the fixed fees twice. London has no city tax; VAT is in the rate. Three of our London hotels, The Ned, Sea Containers London and The Standard, add a discretionary or optional 5% service charge to the room at the hotel.

What we learnt searching 49 hotels for one family on one night.