The London weeks to avoid (or book early for)

Send someone to London on Marathon Sunday without warning them and they'll spend the afternoon in a taxi going nowhere. A handful of weeks every year fill central London with visitors, close roads or both, and any trip that lands in one costs more and takes longer, so check the calendar before you look for somewhere to stay. Smart corporate stays start with the dates, not the address.

Spring and summer

The London Marathon is on a Sunday in spring, usually late April. Roads close along the route from Greenwich through the City to The Mall, so airport runs and weekend arrivals that day need planning around it. In late May the RHS Chelsea Flower Show takes over the grounds of the Royal Hospital Chelsea for a week, Chelsea, Belgravia and Sloane Square get crowded, and apartments nearby go early.

London Tech Week is in June at Olympia in West Kensington and brings a big international crowd, so if a visitor needs to be in Kensington that week, book the moment the dates are out. Wimbledon follows from late June into July. The tennis is a long way from the centre, but the fortnight lands in the middle of peak summer, when central London is at its fullest anyway.

Carnival, fashion and Frieze

Notting Hill Carnival takes over the streets of Notting Hill, Ladbroke Grove and Westbourne Park on the Sunday and Monday of the August bank holiday weekend. Roads close, some stations change how they run, and TfL puts up a dedicated travel page every year. Warn anyone staying in Notting Hill or Bayswater, since some will love being in the middle of it and others will want to be well away.

London Fashion Week comes round twice a year, in February and September. In October, Frieze London and Frieze Masters fill a corner of Regent's Park, the Mayfair galleries time their openings for the same week, and Frieze Sculpture runs as a free outdoor show in the park that season. Both bring buyers and collectors who want to stay in Mayfair, Marylebone and St James's, so if your trip is about something else entirely, these are the weeks to stay a bit further out and travel in.

Engineering works, strikes and booking ahead

Tube engineering works mostly happen at weekends and over bank holidays, and TfL's planned closures page lists them well ahead, so check it before booking a Saturday or Sunday arrival from Heathrow. Strikes are usually announced in advance too; if one falls in the week of a trip, move meetings closer to the apartment or book a car for the airport.

A shared calendar with these weeks marked a year out, sitting next to the company's own fixed points such as results days, board meetings and the sales conference, does more than any clever tool. When a trip request lands on one of them the travel team knows to book that day, and travellers soon learn to suggest the week either side. Update it each January, since most organisers publish next year's dates months ahead and checking takes ten minutes.

In an ordinary week a couple of weeks' notice will often find a good apartment, but for the weeks above, book the day the trip is confirmed. Location matters more than usual when roads are shut. Nearly all the residences we list are within about ten minutes' walk of a station, and on Carnival Monday or Marathon Sunday that's the difference between an easy journey and a taxi stuck behind a barrier.

Build prep time into the itinerary before the big meeting, and one free hour after it. The National Portrait Gallery is just off Trafalgar Square and free to get into, which makes it an easy stop between meetings in Westminster or the West End, and a walk along the South Bank after dark does the same job for nothing.