London Luton airport primarily services European and low-cost airlines. If you arrive to Luton airport, there are several ways to get to Central London.
There is connection by Thameslink (travel time is approximately 40 minutes). You can purchase tickets online on Thameslink website. Pricing varies, check prices online. Thameslink is especially convenient for those who need to travel to St Pancras International station. There is also a regular rail service, takes around 30 minutes, buy tickets online.
Read more information about rail transportation options at London Luton airport website.
Please allow enough time for transportation to and from airport, as the trains do not depart directly from the airport and you will need some time to locate the shuttle bus that takes you to London Luton Airport Parkway train station - that's where the trains depart from.
There are multiple bus options that will take you to Central London in about an hour. There are frequent departures. National Express has some of the most convenient connections and arrival/departure points in Central London. Tickets start as low as £5 one way if purchased online. Check other options at London Luton website.
The taxi will cost around £90-100 one way + tip. Use only official taxi stand to hire a taxi.