Heathrow Transfer to London City Airport.

The key element is

We land at Heathrow at 0700

You mean you are scheduled to land at 0700, whether that happens or not is an open question.

I do not see an 1150 LCY-FCO BA flight for March 11 . I do see a 1050 flight.

BA sold it that way so.... assuming your first flight is on time it should be manageable.

Here is link ( hopefully) to LCY website with info on 'how to get here'

https://www.londoncityairport.com/getting-here/Minicab

2 people with one carry-on bag each is about 47GBP for 'minicab' service Me, I would spend the ~$65 and not bother with multiple rail option

2 people with one carry-on bag each is about 47GBP for 'minicab' service Me, I would spend the ~$65 and not bother with multiple rail option

Taking a cab from Heathrow to London City Airport is the worst option, you can guarantee not making your flight that way, the traffic will be horrendous. LCY airport is handy if you're within 'The City' but for anyone else it's a PIA.

If you do land at 07:00 and let's say you are taxied, deboarded, through immigration and in the taxi by 08:30 it could take almost three hours in bad traffic to make the journey to LCY. Considering you need to be at the airport at least two hours before your flight you'll see that a cab is the riskiest choice to make.

The flight is 10.50 from City airport according to the airport and Skyscanner.

You maybe through Heathrow by 8 am, but it’s more likely to be 9-9.30, as this is a busy time for a Monday morning.

You need to be at City at 10am absolute latest.

Travelling by road is your worst option, as it’s likely to be congested. Early Sunday morning, it’s suggesting that it would take over an hour, which I would double for a weekday rush hour journey.

Public transport will be quicker, but it will still take about 90 minutes.

It sounds like a stressful transfer that I wouldn’t be confident of making. You may just about have made the 11.50, but it’s 10.50,. Take the later afternoon BA flight.

not a snowball's chance in July, I'm afraid.

Did BA really sell this as one ticket? It seems really convoluted. It wasn't you adding the second flight on?

Could this be confusion because USA goes to "summer time" on March 10, but the UK does not until March 31?
tfl says be on the 8:48 Heathrow Express and at be at LCY by 9:55 on the route emma gave in her first post. Later than that can be trouble.

JC, I disagree that London City is a PIA to get to. It’s absolutely my airport of choice and I live in north west London.

Alright, I'll rephrase that. It's a PIA to get to for anyone outside of London ; )

Thanks for all the information. I forgot to say we do not have any checked bags. We travel with carryons. So we don’t have to go to baggage claim.

Baggage claim isn't usually an issue at Heathrow as by the time you've made it through immigration your bags will be waiting for you so having carry on only isn't going to have any affect on the difficulties you face.

I'll weigh in since I have used both airports extensively.

If you have both tickets already then the advice that you won't make it is moot. It is also rush hour and traffic will be terrible. And as everyone said, the plane leaves at 1050 not 1150. That leaves you little time for dawdling.

Once out of immigration and customs at Terminal 5, you have a choice of either the Heathrow Express or the Underground.

The Heathrow Express will take about 1:15 and has three changes.

Step 1
Heathrow Express to London Paddington.

Step 2
Walk from London Paddington rail station to Paddington tube station.

Step 3
DepartPaddington Underground Station via Bakerloo line to Baker Street

Step 4
DepartBaker Street Underground Station via Jubilee line to Canning Town

Step 5
DepartCanning Town DLR Station via DLR to London City Airport DLR Station

The Piccadilly Express way takes about 1:30 and has two changes.

Step 1
DepartHeathrow Terminal 5 Underground Station via Piccadilly line to Green Park

Step 2
DepartGreen Park Underground Station via Jubilee line to Canning Town

Step 3
DepartCanning Town DLR Station via DLR to London City Airport DLR Station

Either way unless you have a contactless phone or credit card you will need to stop to get an Oyster Card.

London City is a small airport. From entrance to security is a two minute walk (up the escalator) and after security it's really no more than 5-7 minutes to any gate.

It will be tight but doable if the gods are on your side.

One other option, there is a noon flight out of Gatwick. To get to Gatwick all you need to do is take a direct bus from Heathrow. (The bus doesn't go into London so traffice won't be as bad.)No changes. Why not call BA, tell them of your concerns regarding time and traffic in regard to changing airports and see if they will change your flight. They might, they might not.