On this page (11 sections)
The realistic options
Kings Cross sits in north-central London, well placed for the airport but not on any of the dedicated Heathrow rail routes. The good news is that you have four realistic ways to get to Heathrow from here, and at least one is right for almost any traveller.
The Piccadilly Line runs direct from Kings Cross St Pancras to every terminal, no change needed. The Elizabeth Line is a short hop or a fifteen-minute walk away at Farringdon, and gets you to the airport faster and just as directly from there. Heathrow Express, the fastest train, needs a connecting Tube to Paddington first, but the combination is still the quickest by rail. A taxi or ride-hailing trip rounds out the choice for travellers with the luggage or the budget for it. The rest of this page sets each option side by side and helps you pick.
Routes compared
The headline numbers below are end-to-end estimates from Kings Cross St Pancras to the central terminal station at Heathrow, including the walk to the platform and any connecting Tube. Add a few minutes for Terminal 5 and a little more for Terminal 4 if your route does not stop there directly.
| Route | Fare | Door to door | Changes | Terminals served |
|---|---|---|---|---|
| Piccadilly Line direct | £5.90 | About 55 min | None | All four |
| Elizabeth Line via Farringdon | £15.50 plus a Tube hop | About 50 min | One short | All four |
| Heathrow Express via Paddington | From £10 advance, £25 on the day, plus a Tube hop | About 40 min | One short | T2, T3, T5 |
| Elizabeth Line via Paddington | £15.50 plus a Tube hop | About 50 min | One short | All four |
| Taxi or ride-hailing | £56 to £105 (cab) | 30 min to an hour | None | All four |
Times are indicative and vary with the Tube, road traffic, and the time of day. Rail fares are pay as you go contactless from zone 1; the daily zones 1 to 6 cap of £16.30 applies to Elizabeth and Piccadilly journeys. Heathrow Express sets its own fares and is outside the cap.
Piccadilly Line direct from Kings Cross
The simplest option. Kings Cross St Pancras Underground sits below the main-line station, and the Piccadilly Line runs from there straight to all four Heathrow terminals. There is no change, the fare is £5.90 with contactless, and trains run every few minutes through the day. The whole trip takes around 55 minutes to the central station for Terminals 2 and 3, with Terminal 5 a few minutes further. Terminal 4 is on a branch that some trains take by way of the Hatton Cross loop.
It is the cheapest train by a wide margin, well under half the Elizabeth Line fare, and it gets you to the airport on a single ticket and a single train. The catch is that it is the slowest of the three trains, and the deep Tube is not the most comfortable place for a large case at peak. For a fuller picture, including the Hatton Cross split and the Night Tube service, see the Piccadilly Line to Heathrow guide.
Via Farringdon on the Elizabeth Line
The Elizabeth Line does not call at Kings Cross, but it stops at Farringdon, one short hop east. From the platforms at Kings Cross St Pancras, take the Circle, Hammersmith and City, or Metropolitan line one stop to Farringdon (about three minutes on the train), then switch to the Elizabeth Line. From Farringdon, the Elizabeth Line runs direct to Heathrow Terminals 2 and 3 in around 38 minutes, and direct to Terminal 4 or Terminal 5 on the trains that continue west to each of those branches.
End to end, allow about 50 minutes including the change. The cost is £15.50 for the Elizabeth Line portion plus the Tube hop, capped at the zones 1 to 6 daily cap of £16.30, so the total is rarely more than the cap. It is the best balance of speed, price, and reach for most travellers, and the right choice if you are flying from Terminal 4.
If you have time and not too much luggage, you can also walk from Kings Cross to Farringdon in about fifteen minutes, straight down Gray's Inn Road or via Clerkenwell Road. Full detail on the line is on the Elizabeth Line to Heathrow page.
Via Paddington on Heathrow Express
The fastest combination. Take the Circle or Hammersmith and City line from Kings Cross St Pancras straight to Paddington, about 13 minutes on the Tube without changing, then switch to Heathrow Express. The train covers Paddington to the central terminals in 15 minutes, so end to end you are looking at about 40 minutes including the change and a walk at each end. Terminal 5 adds about five minutes.
The price is the trade. A standard Express single bought on the day is £25, plus the cost of the Tube hop. Booked well ahead, the Advance Discounted single drops to £10, which makes the whole trip cheaper than the Elizabeth Line via Farringdon if you plan in advance. Heathrow Express does not serve Terminal 4 directly, so passengers for T4 should change at the central station onto the Elizabeth Line or take the free inter-terminal transfer, adding fifteen minutes. See inter-terminal transfer for the practical detail.
Via Paddington on the Elizabeth Line
The forgotten middle option. Once you are at Paddington, you can take the Elizabeth Line as well as Heathrow Express; both leave from there. It is slower than Heathrow Express, at about 30 minutes from Paddington against 15, and it costs the same flat £15.50 as the Farringdon route. So why bother?
Two reasons. If you turn up at Paddington and the next Heathrow Express is more than 15 minutes away, the Elizabeth Line is usually the quicker train to catch. And if you have already gone to Paddington for another reason, you avoid the extra journey out to Farringdon. For most planned trips, the Farringdon route is more efficient, but this fallback is useful to know.
Taxi or Uber from Kings Cross
A black cab from Kings Cross to Heathrow is typically £56 to £105, with the trip taking 30 minutes to an hour depending on traffic and which terminal you are heading to. Ride-hailing apps such as Uber tend to come in cheaper off-peak, often around £40 to £70, but surge pricing on busy evenings or in poor weather can push them well above the black cab fare.
Road travel suits a few specific cases: a group of three or four splitting the cost, a family with heavy luggage and small children, a late-night arrival outside the Night Tube hours, or a traveller who simply prefers door to door. For most solo or paired travellers in the daytime, the train is faster and far cheaper. The wider Heathrow taxi guide covers the booking choices and the pick-up arrangements at the airport.
Arriving on the Eurostar at St Pancras
St Pancras International is the building next door to Kings Cross, and the two share an underground station. Eurostar arrivals come into the lower level of St Pancras, with passport control and customs on the same level. Follow signs for the Underground; the walk to the Piccadilly Line platforms is about five minutes, level for most of it, with lifts available.
Every option on this page applies the same way from St Pancras International. The Piccadilly Line is the natural fit if you want a single train and have time. The Elizabeth Line via Farringdon adds the short Tube hop. Heathrow Express via Paddington is the fastest if you are pressed and willing to pay. With Eurostar luggage and possible jet lag, the Elizabeth Line via Farringdon is often the right balance: one short change, level boarding, and a spacious main-line train for the airport leg.
Which to choose
A quick guide by traveller and situation:
- On a budget, with time to spare: the Piccadilly Line direct, £5.90 and no change.
- Travelling light, fastest by rail: Heathrow Express via Paddington, especially with an advance ticket.
- Most travellers, most trips: the Elizabeth Line via Farringdon. Best balance, all terminals, level boarding.
- Flying from Terminal 4: the Elizabeth Line via Farringdon, the only fast direct route.
- Eurostar arrival with luggage: the Elizabeth Line via Farringdon, or a taxi if you are not far from off-peak.
- Group of three or four splitting a fare: a black cab or Uber can match rail per head, with door to door convenience.
- Late at night or weekend small hours: the Piccadilly Line, the only train running through the night on Friday and Saturday. A taxi otherwise.
- Tight connection at Heathrow: Heathrow Express, the fastest end to end and the most reliable on time.
For the broader case across all transfer modes, including coach and the wider airport transfers, the road-and-rail comparison on the parent hub may be useful too.
Step-free routes
Step-free is reliable for the Elizabeth Line and at the Heathrow stations, less so on the rest of the Piccadilly Line. Kings Cross St Pancras Underground is step-free from street to platform, as are St Pancras International, Farringdon, Paddington, and all three Heathrow rail stations.
The Heathrow Express train and the Elizabeth Line trains have level boarding between platform and carriage at both ends of the route. The Piccadilly Line is step-free at Kings Cross St Pancras and at the Heathrow stations, but many of the stations in between are not, which only matters if you change trains; on the direct journey from Kings Cross to Heathrow you do not. For the full picture and any current changes, check the Transport for London step-free access guide.
When something goes wrong
Because three different trains and the road network all serve this route, you usually have a backup. If the Piccadilly Line is suspended, the Elizabeth Line via Farringdon is unaffected and runs on entirely separate tracks. If Heathrow Express has engineering work, the Elizabeth Line from Paddington picks up most of its passengers. If both Tube lines from Kings Cross are down, a black cab or a ride-hailing trip gets you to the airport, though usually more slowly than rail.
Before you travel, check the live position. The Transport for London service status page covers the Underground and the Elizabeth Line, and the train disruption page on this site collects the current notices across all three rail routes.