Most Heathrow connections work just fine. The ones that do not, fail for the same reason: people do not understand their connection type before they land. That is how you miss a flight at Heathrow. This guide fixes that.

At Heathrow, your connection type matters more than your connection time. The number one thing people get wrong: assuming their connection time is fine because the airline sold them the ticket. The airline’s minimum and your comfortable minimum are not the same number. Know your connection type before you book.

Here is the answer most people are looking for:

What is your situation?

• “Both my flights are BA within Terminal 5. What do I do when I land?” → BA to BA Within Terminal 5
• “I am arriving on a different airline. How do I get to BA’s terminal?” → Arriving On Another Airline And Connecting To BA
• “I booked my flights on separate tickets. What does that mean?” → Separate Tickets: The Risk You Need To Understand
• “My layover is under 90 minutes. Is that enough time?” → Is My Layover Long Enough?
• “My onward flight is from Gatwick. How does that work?” → Connecting From Heathrow To Gatwick
• “I missed my connection. What happens now?” → What Happens If You Miss Your BA Connection?

Connection Times At A Glance

These are minimum realistic times under normal conditions. A delayed inbound, a gate in T5C, or a peak-hour security queue all add time. Always give yourself more buffer than the minimum.

If you remember one thing from this table: most Heathrow connections work, as long as you understand your connection type.

BA to BA Within Terminal 5

If both flights are British Airways and booked on the same ticket, this is one of the easiest connections you will make at a major European airport. If your inbound flight is on time and you follow the signs, you will make this connection. That is the reassurance. Here is what it actually looks like on the ground.

Step 1: Follow The Purple Signs.

The moment you deplane, look for the purple Flight Connections signs and follow them. Do not follow arrivals signs. That is how people accidentally exit the airport and lose 45 minutes. Do not go toward baggage claim. The purple signs are your only route. At T5, every corridor looks similar, and the signs are the only thing that keeps you oriented.

Step 2: Take The Transit Train If You Landed At T5B or T5C.

Terminal 5 is three buildings connected by an underground automated train. If your inbound flight lands at T5B or T5C, you need to take the transit back to T5A before you reach Flight Connections security. The train runs every 4 minutes. Budget 10 to 15 minutes for the walk and the wait.

Step 3: Clear Flight Connections Security.

This is a separate security lane from the main departures hall, and it moves faster in most cases. You will re-screen here. Check current Heathrow liquids rules before you travel, as the policy has updated in recent years.

Step 4: Check The Departure Boards.

After security, check the departure boards for your gate. Gates are not assigned until closer to departure. Do not assume your gate from your boarding pass alone. It may have changed.

Step 5: Factor In The Transit Train Again If Your Onward Gate Is In T5B or T5C.

This is the step most people underestimate. A gate deep in T5C from T5A security is not a quick walk. It means the transit train and a long concourse. Add 15 minutes to your mental plan if your onward gate is in the satellite buildings.

If your inbound is on time and you keep moving, this process works exactly as described.

The official minimum connection time for most BA to BA T5 connections is 75 minutes, increased from 60 minutes in January 2024. A comfortable connection is 90 to 120 minutes. If your connection is under 75 minutes and booked on one ticket, BA will still sell it to you – but you should know the margins are tight.

If you have time between connections, here is which BA lounge to use at Terminal 5 → Which British Airways Lounge Should You Use At Heathrow?

Q: What is the minimum connection time for British Airways at Heathrow Terminal 5?

A: The official minimum connection time for BA to BA connections within Heathrow Terminal 5 is 75 minutes, increased from 60 minutes in January 2024. This is the minimum BA will sell on a single ticket. A comfortable connection is 90 to 120 minutes, particularly if your arriving or departing gate is in T5B or T5C, which require an additional transit train ride of 10 to 15 minutes.

If both your flights are BA within T5, that is the straightforward scenario. The connection that catches most people off guard is arriving on a different airline.

Arriving On Another Airline And Connecting To BA

Two things people worry about when arriving on another airline and connecting to British Airways at T5: having to go through passport control, and having to collect their bags. In most cases, you do not have to do either. You do not need to enter the UK or go through passport control for this connection. And if your bags are checked through to your final destination, you do not need to collect them at Heathrow. Stay airside and follow the signs.

Here is how the transfer actually works.

Most major international airlines use Terminal 2 or Terminal 3 at Heathrow. If you are arriving from the United States on American Airlines, United Airlines, Delta, or a Star Alliance carrier, you are almost certainly landing at T2 or T3. After you deplane, follow the purple Flight Connections signs. They will lead you to the dedicated airside Flight Connections bus between terminals.

The bus is free, runs every 6 to 10 minutes, and does not require you to go through any immigration or customs. The journey takes around 10 to 15 minutes. Add walking time on both ends and you are looking at 20 to 30 minutes of transit in good conditions.

Once you arrive at T5, follow the purple signs to Flight Connections security. You will clear security here before accessing T5’s departures area. After that, you are effectively a normal departing passenger at Terminal 5.

The official minimum for T3 to T5 on a same-ticket connection is 90 minutes. Two hours is where you stop watching the clock.

One important distinction: this only works smoothly if your flights are on the same ticket or a recognized codeshare itinerary. If they are on separate tickets, you cannot take the airside bus. You must go through baggage claim, clear customs, and re-check in from the landside. That is a completely different process.

The Flight Connections bus is one of the least-known useful things at Heathrow. Most first-time connectors have never heard of it and end up in arrivals by accident. 

Full inter-terminal transfer guide → How To Transfer Between Terminals At Heathrow

Q: How do I connect from Terminal 3 to British Airways at Terminal 5 at Heathrow?

A: Follow the purple Flight Connections signs from your arrival gate at Terminal 3. Take the free airside Flight Connections bus to Terminal 5, which runs every 6 to 10 minutes. Clear Flight Connections security at Terminal 5 before accessing the departures area. Do not go to baggage claim or exits unless instructed. The official minimum connection time for T3 to T5 on the same ticket is 90 minutes. Two hours is a comfortable buffer.

Separate Tickets: The Risk You Need To Understand

This is the most expensive mistake people make at Heathrow. This is not a maybe. It is a known risk with a known outcome. If you have booked two flights on separate tickets and your connection is tight, you need to understand exactly what you are exposed to before you are standing in baggage claim wondering what happened.

If your flights are on separate tickets and you miss your connection, the second airline has no obligation to rebook you. You will need to buy a new ticket at whatever the current fare is. On a transatlantic or long-haul route, that can run into the thousands.

Here is the full process you must complete on separate tickets:

Collect your checked bags from baggage reclaim. Clear customs and UK border control, which can take 30 to 60 minutes at peak times. Exit to the landside area. Re-check your bags for your onward flight, subject to that airline’s check-in cutoff (usually 60 minutes before departure). Clear departures security from scratch.

BA’s own guidance for passengers connecting on separate tickets: allow a minimum of 4 hours. That is the airline’s own recommendation, not a conservative estimate from a travel blog.

The one scenario with a little more flexibility: if you have no checked bags and both flights are within T5, the practical minimum drops to around 2 to 3 hours. Under 2 hours on separate tickets, even without bags, is a gamble.

Separate Tickets Means Separate Responsibility. If your inbound is delayed by 45 minutes and your connection is 2 hours, you may still make it physically. But if you do not, you are buying a new ticket out of pocket. The airline that delayed your inbound is only responsible for the ticket you bought from them.

If you cannot build 4 hours of buffer into a separate-ticket connection at Heathrow, the economics of the cheaper fare rarely survive the cost of buying a replacement ticket. Reconsider the routing.

Q: How much time do I need to connect at Heathrow on separate tickets?

A: British Airways recommends a minimum of 4 hours when connecting at Heathrow on separate tickets, as you will need to collect bags, clear UK border control, and re-check in for your onward flight. There is no airline protection if you misconnect on separate tickets. You are responsible for any costs of re-booking.

Is My Layover Long Enough?

By this point, you should know your connection type. Now the only question is whether your timing works.

Here are the verdicts, not a framework:

• 90+ Minutes On One Ticket, T5 to T5, Inbound On Time: You are fine.
• 75 Minutes On One Ticket, T5 to T5: Tight but workable. Do not check a bag you do not need to.
• Under 60 Minutes On One Ticket, T5 to T5: Expect problems. Have a plan B.
• Under 60 Minutes On Separate Tickets, T5 to T5: Do not do this.

One reality check that most people miss: the majority of missed connections at Heathrow happen because the inbound flight was late, not because the connection time was too short on paper.

The variables that eat your buffer fastest, in rough order:

• A delayed inbound flight is the biggest factor.
• Then arriving at T5C when your departure is from T5A (add 15 minutes of transit).
• Then a long security queue at Flight Connections during the morning peak wave from around 6am to 9am.
• Then not having a boarding pass for your onward flight already loaded on your phone (adds time at kiosks).

If you misconnect on one ticket, BA will rebook you on the next available service at no cost. You may wait several hours depending on the route and availability. That protection is the entire reason booking on one ticket matters.

What actually happens if you miss your BA connection →

Connecting From Heathrow To Gatwick

This is not a connection. It is a transfer between two separate airports 30 miles apart. Everything that follows makes sense once you understand that.

Heathrow [LHR] and Gatwick [LGW] are different airports in different locations. Getting between them is not like changing terminals. It is a full airport transfer with a coach journey through London traffic, a full bag collection, customs clearance, and a new check-in process on the other side.

Here is what you actually have to do:

Collect all your checked bags from baggage reclaim at Heathrow. Clear customs. Take the National Express coach from Heathrow to Gatwick, which takes between 45 and 90 minutes depending on traffic. Check in at Gatwick for your onward flight, subject to that airline’s check-in cutoff.

The official minimum connection time for Heathrow to Gatwick is 3 hours. The coach journey alone can eat 90 minutes. Allow 3.5 to 4.0 hours to be comfortable.

If you are on one ticket, BA has an obligation to get you to your destination if your inbound is delayed. They will rebook you. On separate tickets, a traffic-delayed coach that causes you to miss your Gatwick flight is entirely your responsibility.

If you have a Heathrow-to-Gatwick connection with less than 3 hours, check your itinerary carefully. British Airways sets its own minimum at 3 hours. Less than that is not a viable connection under normal conditions.

Q: How do I connect from Heathrow to Gatwick for a British Airways flight?

A: Collect your checked bags at Heathrow, clear customs, and take the National Express coach to Gatwick, which takes 45 to 90 minutes depending on traffic. The official minimum connection time for Heathrow to Gatwick is 3 hours. Allow 3.5 hours to be comfortable. Heathrow and Gatwick are separate airports approximately 30 miles apart.

What Happens If You Miss Your BA Connection?

First: do not panic. You are not the first person this has happened to today.

If your flights are on one ticket and you missed your connection because your inbound was delayed or you simply ran out of time, you are protected. Go directly to the British Airways customer service desk. In T5, the desk is in the Flight Connections area before security. In T3, it is after security. BA will rebook you on the next available service at no charge. If the wait is significant, they are required to provide meal vouchers. For overnight delays, hotel accommodation is included.

If your flights are on separate tickets, the process is different. Go to the British Airways check-in desk or ticket office. You will need to purchase a new ticket. Travel insurance that covers missed connections may reimburse you, but the purchase is yours to make in the moment.

Two things worth knowing if you are on a delayed inbound and running tight:

Tell the cabin crew before you land. They can alert the gate for your connecting flight, and occasionally the departing aircraft will hold for a small number of connecting passengers. It is not guaranteed, but it happens more often than most people realize.

Look for the time-critical connections screens in the connections area at T5. These screens flag flights that have passengers in urgent connection situations. If your name is on one, staff will often meet you at the gate.

BA flight disruption: your rights and what to do →

Three Mistakes That Cause Most Missed Connections at Heathrow

These are the three mistakes that cause most missed connections at Heathrow.

Mistake 1: Following Arrivals Signs Instead Of Flight Connections Signs.

Once you are in baggage claim, you cannot go back. You have committed to entering the UK, and you cannot re-enter the airside connections area without going through full arrivals processing. That adds a minimum of 45 minutes to any connection. The purple flight connections signs are your only route from the moment you deplane. They are not optional reading.

Mistake 2: Assuming “Same Airline” Means “Same Ticket.”

A codeshare itinerary where both flights show a BA flight number can still be on two separate tickets. Check your booking reference. If you have two different booking references, you are on separate tickets regardless of what the flight number says. The implications of that, in terms of bag collection and missed connection protection, are covered above.

Mistake 3: Not Knowing Your Gate Cluster Before You Connect.

A gate in T5A and a gate in T5C are not the same experience. Landing at T5C and departing from T5A means a transit train, walking through T5A, Flight Connections security, and then possibly the transit train again for your outbound gate. That sequence takes 30 to 40 minutes under good conditions. Most people discover this for the first time when they are already running.

Final Thoughts

Your connection type is the thing that determines everything at Heathrow. More than the terminal, more than the lounge, more than the time on your boarding pass. Get that right before you book, and Heathrow becomes predictable. Get it wrong, and everything else starts to break.

Back to the complete BA at Heathrow guide → British Airways At Heathrow: The Complete Terminal 5 Guide [2026]

Full Terminal 5 layout, gates, and security →

Updated for 2026. Check back if British Airways updates its minimum connection times or T5 security policy changes.

Kevin Zanes