The most direct route is the Piccadilly line, which runs straight from Heathrow to King's Cross St Pancras with no change in about 55 minutes, for around £5.60 to £5.90 with contactless. St Pancras International, where the Eurostar departs, is right next door. Allow roughly 3.5 hours from landing to your Eurostar departure to be safe. Checked August 2026.
The direct option: Piccadilly line
The Piccadilly line Tube runs directly from Heathrow to King's Cross St Pancras, and the Eurostar terminal at St Pancras International is a short covered walk from the Tube station, so you stay under one roof at the London end. It is also the cheapest way in, from about £5.60 to £5.90 with a contactless card or Oyster, charged at the peak rate at all times because there is no off-peak discount to Heathrow.
Journey time is roughly 54 to 56 minutes from Terminals 2 and 3. From Terminal 4, allow closer to 69 minutes because it is a separate station on the south side. Trains run about every 5 to 10 minutes from around 05:00 to 23:30, with the Night Tube running all night on Fridays and Saturdays. The trade-off is that the Piccadilly line makes many stops and can be busy, so with heavy luggage you may prefer the faster mainline option below.
The faster option: Heathrow Express then a short hop
If you want speed, take the Heathrow Express to Paddington (15 minutes from T2 and T3, or 21 minutes from T5), then change onto the Elizabeth line or the Circle and Hammersmith and City lines to King's Cross St Pancras. The Express is £26 walk-up, or from £10 if you book 30 or more days ahead, and children 15 and under travel free with a paying adult. This route can shave time in the middle of the day, but it adds a change and a fare, so weigh the saved minutes against the extra cost and hassle with bags.
The Elizabeth line is a middle path: £15.50 to Zone 1, direct to Farringdon in around 35 minutes, then one stop on the Metropolitan, Circle or Hammersmith and City line to King's Cross St Pancras, or a short walk. It is cheaper than the Express and faster than the Piccadilly line, at the cost of one interchange.
| Route | Time to St Pancras | Single fare | Change needed |
|---|---|---|---|
| Piccadilly line | About 55 min | £5.60 to £5.90 | None |
| Elizabeth line via Farringdon | About 40 to 45 min | £15.50 | One |
| Heathrow Express via Paddington | About 30 to 40 min | £26 walk-up (from £10 advance) | One |
How much time to allow
This is the part people get wrong. Eurostar is an international service with its own check-in, security and passport controls, so you cannot arrive at the last minute. Eurostar generally advises being at St Pancras well before departure, and check-in closes ahead of the train, so plan to arrive at least 60 to 90 minutes early. Confirm your exact check-in cut-off with Eurostar, as it varies by fare and can change.
Working backwards from that, allow a comfortable buffer from the moment you land at Heathrow:
- Clearing UK passport control and reaching the Tube: this can be quick with eGates but a long-haul peak can add time.
- The train into St Pancras: about 55 minutes on the Piccadilly line, plus waiting.
- Eurostar check-in and controls: at least 60 to 90 minutes.
Add it up and you want roughly 3.5 hours between landing and your Eurostar departure, more if you are checking a bag through immigration or travelling at a busy hour. If you are only changing from one train to another (not arriving on a flight), 2 to 2.5 hours from central Heathrow is a sensible minimum.
A note on immigration
If you are connecting from an international flight, you must clear UK immigration to leave the airport and board the Eurostar, and you may need a UK ETA or a visa to enter the UK even for a short stop. Check your status before you rely on this route. See our guide to Heathrow entry requirements.
More
More: Overview, Public transport, FAQs.
Frequently asked questions
Is there a direct train from Heathrow to St Pancras? Yes. The Piccadilly line runs direct from Heathrow to King's Cross St Pancras with no change in about 55 minutes, and St Pancras International is next door.
How long does Heathrow to St Pancras take? About 54 to 56 minutes on the Piccadilly line from Terminals 2 and 3, or nearer 69 minutes from Terminal 4. The Elizabeth line via Farringdon is a little faster with one change.
How much time should I allow for the Eurostar? Aim to be at St Pancras at least 60 to 90 minutes before departure for check-in and controls, and allow about 3.5 hours in total from landing at Heathrow. Confirm the check-in cut-off with Eurostar.
What is the cheapest way from Heathrow to St Pancras? The Piccadilly line, from about £5.60 to £5.90 with contactless. It is direct but makes many stops and can be busy.
Do I need to clear UK immigration to catch the Eurostar from Heathrow? Yes, if you are arriving on an international flight you must clear passport control to leave the airport, and you may need a UK ETA or visa to enter.
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Last verified August 2026 by the Heathrow Airport Guide editorial team. Prices and timetables change, so confirm the specifics on the official Heathrow Airport website before you travel.