If you are coming to the area by Underground, the best station to arrive at is Notting Hill Gate (located on the road of the same name) which is on the Central, Circle and District Lines.
Other stations in the nearby area include Ladbroke Grove, Westbourne Park and Royal Oak stations (all Hammersmith & City Line) to the west/north-west.
There are also many buses operating across the whole of Notting Hill, including routes 27, 28, 31, 52, 70, 94, 328 and 452 amongst others. Take a look at Transport for London’s Kensington & Chelsea Bus Route maps for more details.
The closest airport to Notting Hill is Heathrow Airport. From there you can either travel by Underground or train into Notting Hill and Central London. By Underground, take the Piccadilly Line all the way to Earl’s Court, before changing to the District Line (two stops to Notting Hill Gate). By train, take the Heathrow Express to Paddington Station, before changing for the District Line on the Underground (two stops to Notting Hill Gate).
Transport for London website
Includes maps and a very useful journey planner