Can I leave LHR while transiting from CDG to SIN?

[dsotm]

Looking at booking a Classic J Reward from Paris to Singapore then picking up a paid economy onto Melbourne (no availability ob rewards). There's a 7-hour layover in London. The flight would be a BA codeshare (BTW, where have all the Qantas J CR's from Europe gone?!!!). Can I leave Heathrow for the afternoon and my bags will be checked from CDG to SIN?

 

[defurax]

Yes, no problem leaving. I actually technically "leave" LHR on almost all my transit from T3 to T5 as I'd rather go through automated passport kiosk at immigration, take the free Heathrow express to T5 and go to the BA First Wing security screening. It's faster than transit security at T5.

 

[dsotm]

Yes, no problem leaving. I actually technically "leave" LHR on almost all my transit from T3 to T5 as I'd rather go through automated passport kiosk at immigration, take the free Heathrow express to T5 and go to the Wing First security screening. It's faster than transit security at T5.

Great! Many thanks.

 

[tdimdad]

I've made a habit for myself to escape the airports to the city when the connection time allows. Tested it in London back in 2008 and had a stroll around the Kensington Park and surroundings - a much nicer way to spend time than loitering at the airport. Since then I've done other cities, too.
Just make sure you return back to the airport early enough to clear the security even if there was a lengthy queue to it.

 

[OATEK]

I took the Elizabeth line train to/from Paddington during a long transit in August (arrived T3, and departed later from T5). Easy enough to do. Security cab be slow so allow a good period for re-entry. I left a bag at the left-luggage in T5.