How much time does it take to travel between terminals at heathrow airport?

Getting to Terminal 5 from Terminal 3 involves a seemingly long bus ride; I'd expect at least 45-60 minutes for bus ride and passport control. Then, you will go through a security line again in Terminal 5.
Safe travels!

thank you!

Is this a true connecting flight, meaning the flights are on one ticket? If so, you do not go through immigration upon arrival in T3; you stay airside and transfer between T3 and T5 on a special bus. It does not take long; we did it last May and the bus ride was less than 15 minutes. But then you have to go thru security in T5 and find your way to your gate.

The minimum connect time for this is 90 minutes, but I want more than that, like 2 hours.

If the flights are not on one ticket, then it is a different matter.

Thank you for your response. Our flights are on separate airlines and will not be connected. Do you think 3 hours in between landing and a connecting flight would be sufficient? We have not booked our connecting flight yet.

Question- checked or carry-on luggage?
There's no way to connect the flights with the airline codeshares?
Safe travels!

The baggage question is crucial.

With carry-on only, if you get your boarding passes ahead of time ( check in online 24 hours ahead of the second flight's departure in UK time), you can still connect between the terminals airside. That way you avoid going through passport control in T3. You would follow the purple "flight connections" in T3 to the bus that takes you to T5. You will still have a security check there.

If you have checked bags, you will have to go through passport control, technically entering the UK to get to baggage claim in T3. Pick up your bags, and transfer "landside" to T 5 using the Heathrow Express train ( it is free for this short journey). See the instructions here under "not a connecting passenger?":

https://www.heathrow.com/at-the-airport/airport-maps/travel-between-terminals

You will reach T5 in a few minutes, and go up to the departure concourse to re-check bags, and then proceed to security there. After security you will be in the main shopping and dining area and you hang out there until your gate is posted. That may not be until an hour (or less) before the flight. Head to the gate once it is posted.

As for the time needed between flights on separate tickets, I consider 4 hours the minimum at Heathrow. We have done separate tickets on two occasions, and so far we have never needed that much, but it is better to have extra time than to miss the second flight.

Thank you for your advice! This has been very helpful. We will have carry on bags only, that should help.

Your inbound flight on DL could run late as my most recent flight in late October was delayed around 90 minutes. There could be a delay at baggage claim at Terminal 3. Security lines at Terminal 5 could be extensive & slow.

When I do a layover at Heathrow from DL to BA, I allow a minimum of 4 hours. If you miss that BA flight, the return flight back to Heathrow or any other flight on that itinerary will automatically be cancelled.

Thank you! I think we will schedule our connecting flight at least 4 hours after our DL flight arrival time.

Depending on your origin and time of year, do factor in potential weather delays of your departure flight.

If I know I am making the T3-T5 shuffle, I plan 90 minutes for the transfer. Even if the transfer goes quicker than that, its a good rule of thumb as some of the T5 gates are at a satellite terminal which can be another 10-15 minutes away.

One other note that may help. The UK now has automatic gates that can be used for immigration. I just did this in December. Landed in T3, transfered to T5 for a BA connecting flight. First electronic gate is for your passport. Stand on the "mark" (painted feet), put your passport picture page on the scanner, and look into a camera. After a few seconds, the gates open. There will be staff there to help with this. If you wear glasses, make sure you take them off when you look into the camera or you will be delayed. When the gates open, you will be shunted into a small walkway to a second set of gates where you scan your boarding pass (works a bit like a TSA scanner). Once that is done, the gates will open and you will go through T5 security. The system does seem to work well - where you may hit a delay is in the actual security line. Traveling with only carry-ons is a huge help.

I have to say I am stunned that people are taking this much time and effort to answer what I thought was a simple question. The quality of information provided and the time it took to share it are greatly appreciated! Just shows there are good people everywhere, thank you all for being so kind and generous.