Passengers travelling between central London and Heathrow Airport have two principal rail options: the dedicated Heathrow Express and Transport for London’s Elizabeth line.

Both use the same railway between Paddington and Heathrow, but they offer very different journeys.

The Heathrow Express runs non-stop from Paddington and reaches the airport in as little as 15 minutes. The Elizabeth line is slower because it calls at intermediate stations, but it serves several parts of central London directly and generally costs less when purchased on the day.

Choosing between them depends on where you are starting, how much luggage you have, which terminal you need and whether you booked your ticket in advance.

Fares and schedules change, so we urge The Flight Edit readers to check the relevant operator before travelling.

From Paddington, the Heathrow Express is the clear winner.

The non-stop service takes approximately 15 minutes to reach Heathrow Central, the station serving Terminals 2 and 3. Passengers travelling to Terminal 5 remain on the train for around another six minutes.

By comparison, the Elizabeth line takes approximately 27 minutes between Paddington and Heathrow Central because it calls at stations including Ealing Broadway, West Ealing, Hanwell, Southall and Hayes & Harlington.

That makes the Heathrow Express roughly 12 minutes faster when comparing the trains from Paddington alone.

However, this does not necessarily make it the quickest option for the complete journey.

A passenger starting near Liverpool Street, Farringdon, Tottenham Court Road or Bond Street can board the Elizabeth line and travel directly to Heathrow. Choosing the Heathrow Express would require reaching Paddington first, changing trains and potentially walking between platforms.

Once that transfer is included, most passengers beginning their journey east of Paddington will find the Elizabeth line equally fast or faster overall.

The Heathrow Express makes the most sense when you are already at Paddington, staying nearby or arriving there on a Great Western Railway service.

The answer depends on when you buy the Heathrow Express ticket.

An Elizabeth line journey between Heathrow and Zone 1 currently starts from £13.90. Passengers can use contactless payment or an Oyster card without buying a ticket in advance.

A standard Heathrow Express single purchased on the day costs considerably more, at £26. Simply tapping a contactless card at the barrier does not unlock the promotional fare, instead the full Heathrow Express price will be charged.

However, Heathrow Express sells Advance Discounted Single tickets from £10 when booked at least 30 days before travel.

That creates an unusual situation: Heathrow Express can be both faster and cheaper than the Elizabeth line if the journey is booked early enough.

The £10 advance fare is subject to availability and must be purchased before travelling. Anyone arriving at Paddington without a discounted ticket will normally find the Elizabeth line considerably better value.

Families should calculate the total cost rather than comparing the adult fare alone.

Children aged 15 and under travel free in Heathrow Express Standard Class when accompanied by a paying adult. A child ticket is still required, but this can make Heathrow Express unexpectedly competitive for a family.

On Transport for London services, children under 11 can generally travel free with a fare-paying adult, while older children require an appropriate ticket, Oyster photocard or other concession.

The Heathrow Express provides the better environment for passengers carrying several suitcases.

Its trains are designed specifically for airport journeys and include dedicated luggage racks. Standard Class also provides tables, charging sockets, Wi-Fi and toilets.

The wider doors and dedicated storage reduce the need to keep a large suitcase directly beside your seat.

The Elizabeth line has spacious walkthrough trains and accessible areas, but it is ultimately part of London’s commuter network. Luggage space is less clearly defined, and large cases may need to remain beside you or close to the doors.

This is normally manageable outside the busiest periods. During the morning and evening peaks, however, the Elizabeth line can become extremely busy as it carries commuters across London.

Passengers with several large cases, sports equipment or young children may find the Heathrow Express calmer and easier – particularly when boarding at Paddington, where the train begins its journey.

For somebody travelling with one cabin bag, the difference is unlikely to justify paying the full £26 walk-up fare.

Heathrow Express trains normally leave Paddington every 15 minutes, giving passengers four departures per hour.

The regular timetable is easy to remember, and the trains operate non-stop between Paddington and Heathrow Central.

Elizabeth line services also operate several times per hour, but Heathrow trains are divided between Terminal 4 and Terminal 5 branches. Not every westbound Elizabeth line train travels to the airport, and some terminate at destinations such as Hayes & Harlington, Maidenhead or Reading.

Passengers should check the destination displayed on the platform before boarding.

The combined Elizabeth line service across central London is extremely frequent, but a passenger waiting for a specific Heathrow terminal may have a longer gap than the general line frequency suggests.

Engineering work can affect both services because Heathrow Express and the Elizabeth line share railway infrastructure between Paddington and the airport. It is worth checking the TfL journey planner before setting out, especially early in the morning, late at night or at weekends.

Passengers flying from Terminal 2 should leave either service at Heathrow Central, also called Heathrow Terminals 2 & 3 station.

From the station, Terminal 2 is reached using the pedestrian walkways. Allow additional time to travel from the platform to the check-in area, particularly when carrying luggage.

From Paddington, Heathrow Express is fastest. From Bond Street, Tottenham Court Road, Farringdon or Liverpool Street, the direct Elizabeth line will usually be more convenient.

Terminal 3 also uses Heathrow Central station.

The terminal is connected to the station by underground pedestrian routes. The walk can take longer than some passengers expect, so the advertised 15-minute Heathrow Express journey should not be confused with arriving at the check-in desk 15 minutes after leaving Paddington.

As with Terminal 2, Heathrow Express wins on speed from Paddington, while the Elizabeth line is generally more convenient from elsewhere in central London.

The Elizabeth line is normally the better option for Terminal 4 because selected trains serve the terminal directly.

Heathrow Express does not operate a direct Paddington–Terminal 4 service. Passengers must leave the train at Heathrow Central and transfer to a free connecting Elizabeth line service.

The transfer is not especially difficult, but it removes some of the speed advantage offered by Heathrow Express. Waiting for the connecting train can also make the overall journey longer than taking a direct Elizabeth line service from central London.

Passengers using the Elizabeth line must still confirm that their chosen train is operating to Terminal 4. Boarding a Terminal 5 service will take them to a different part of the airport.

Both services operate directly to Terminal 5, although Heathrow Express remains the faster choice from Paddington.

The Heathrow Express journey takes approximately 21 minutes, while the Elizabeth line generally takes around half an hour.

Terminal 5 station is directly beneath the terminal, with lifts and escalators providing access to departures and arrivals.

If you are already at Paddington and have an advance ticket, Heathrow Express is the obvious choice. Passengers travelling from central or eastern London may save time by remaining on one Elizabeth line train instead of changing at Paddington.

A passenger travelling on an Elizabeth line service to Terminal 4 when they require Terminal 5, or vice versa, can transfer between terminals using Heathrow’s free internal transport arrangements.

Rail journeys between Heathrow terminals are free, although passengers using contactless or Oyster may still need to touch in and out correctly.

Heathrow also operates the free H30 bus between Terminals 4 and 5 at certain times.

While changing terminals is possible, it can add considerable time to the journey. Always check the airline and terminal before leaving for the airport, as Heathrow terminal assignments can occasionally change.

The Elizabeth line’s greatest advantage is not price or speed but connectivity.

It provides direct Heathrow services from:

Someone staying near Tottenham Court Road can board one train and remain on it until Heathrow. Taking the Heathrow Express would mean travelling to Paddington, finding the mainline platforms and changing services for a time saving that may disappear entirely.

The Elizabeth line also offers useful connections with other rail and Underground services. Farringdon connects with Thameslink, while Liverpool Street provides access to Greater Anglia services and the Central, Circle, Hammersmith & City and Metropolitan lines.

For most visitors staying in central London, avoiding a transfer with luggage is worth more than saving 12 minutes between Paddington and Heathrow.

Heathrow Express becomes much more compelling for passengers arriving at Paddington on Great Western Railway.

Travellers from Bristol, Bath, Cardiff, Oxford, Reading and other destinations in western Britain can change at Paddington and continue directly to Heathrow.

The same applies to passengers staying in west London or close to Paddington station.

The service is also attractive to business travellers who value a predictable non-stop journey, dedicated luggage storage and a quieter onboard environment.

Premier+ tickets provide additional space and benefits, although most leisure passengers will find Standard Class perfectly adequate for such a short journey.

For most passengers travelling from central London, the Elizabeth line is the better all-round choice.

It is direct from several major London stations, costs less than a walk-up Heathrow Express ticket and removes the inconvenience of transferring at Paddington. Its journey may be slower on paper, but it can be quicker from door to terminal.

Heathrow Express still has a valuable role. From Paddington it is comfortably the fastest option, offers better luggage facilities and provides a more relaxed airport-transfer experience.

Its £26 walk-up fare is difficult to justify for many solo travellers when the Elizabeth line uses the same corridor for considerably less. However, the £10 advance fare changes the calculation completely. At that price, Heathrow Express offers excellent value – and families with children aged 15 and under may also find it surprisingly economical.

The simplest conclusion is that Heathrow Express is best when you begin at Paddington, secure an advance fare or travel with substantial luggage. For almost everyone else, the Elizabeth line is likely to be cheaper, easier and more useful.