See also this thread:
http://www.flyertalk.com/forum/briti...ing-guide.html
For details of suitable hotels for those doing a last flight/first flight turnaround, please see this thread:
http://www.flyertalk.com/forum/briti...rt-hotels.html

Order: Back-to-back Transfer Landside Notes
[so Excellent for back to back usually means an easy airside transfer with few risks]
ABZ: Excellent Excellent if domestic, otherwise Reasonable Reasonable Arrivals decant into departure hall.
ACE: Reasonable if off season, there is a transfer channel just before passports Reasonable Reasonable
AGP: Excellent for Schengen, Risky if not. Schengen - immediate turnaround possible at gate area. Non-Schengen - There is a transit passageway back to airside on the left after passports, but there can be long delays at passports, achievable if you are willing to politely push in the queue.
see here.
ALC: Reasonable if off season, but you do need to go fully airside if non Schengen. Small and efficient airport. Peak time: see here.
ALG: Impractical due to visa and immigration processes. See post 2224.
AMS: Excellent Excellent Poor Arrivals decant into departure hall normally.
ANE: Good - very small airport, tarmac walk. You may want to telephone the airport to let them know since there's no OLCI facility.
ARN: Excellent Good Reasonable (arriving pax should watch for sign to gates 70-82) * see posts 593, 238 & 1298 for more details.
ATH: Reasonable but don't hang about, you need to enter Schengen immigration, then leave Schengen, and a fairly efficient security check. Distances aren't great.
BCN: Good to excellent - bit of a walk - small flight connection facility to the left of passport control, dedicated security but no passports Good if non-Schengen, Reasonable if Schengen Reasonable
BGO: Excellent Excellent Excellent, borderline foolproof though only restricted number of flights Arrivals decant into departure hall.
BHD: Excellent - use stairs upwards between gates 5 and 6, against flow Excellent if domestic, otherwise Reasonable Reasonable
BIO: Reasonable, does involve going landside but small airport, airbridge rather than bus Reasonable Reasonable
BIQ: Reasonable, involves going through passports to landside, security and passports again, but you need to be off early since passport checks are thorough.
BJV: Not really feasible, there is no online check-in or App facility, you must check in at the gate.
BOD: Reasonable but does involve going landside and back again. However it's a small airport and efficient.
BLL: Good (there is a clear transfer route after passport control to avoid a security check Good Good
BLQ: Good (small airport but you have to go landside) Reasonable Reasonable (bus gates)
BRI: Good (small airport but you have to go landside) Reasonable Reasonable
BSL: Good Good Good (Bit of a walk to landside, but it's not a huge airport. See this post for info).
BRU: Excellent on the transfer route, reasonable if not Reasonable Poor (see comments in post #246, also 64 onwards)
CAG: Reasonable, does involve going landside but small airport, airbridge rather than bus Reasonable Reasonable
CDG: Hopeless
CFU: Near impossible, no OLCI, you must present yourself at check-in. Process involves bus, passports, out to landside, short walk to departures building on right, security and bus. Security is bad on peak days.
CGN: No OLCI, but on some dates it is still possible. See this post for details.
CHQ: Near impossible despite being a small airport, no OLCI so you can only get a boarding pass at the airport, and bus to and from gates.
CMB: Easy to do airside. Arriving and departing pax are not segregated. If you have your return boarding pass, just walk directly from arrival gate to departure gate.
CMF: Generally Good, involves going landside. Best avoid Saturdays, the main changeover day, when security is stretched.
CPH: Excellent Good Reasonable Arrivals decant into departure hall.
CTA: Reasonable, there is a transfer route signed but seems obsolete. However small and efficient airport so still do-able if going via landside.
DBV: Impractical - there's no online check in here, you have to go landside and collect a boarding pass. Otherwise a very small airport.
DUB: Good (if ex-LHR), Reasonable if ex-LCY (quicker plane turnaround) Good if Common Travel Area, otherwise Reasonable Reasonable May require passing security, so Fast Track helps. See this post for a photo guide. (As of June 2017 increased risk due to pax segregation at 200 gates and ongoing building work)
DUS: Excellent Excellent if non-Schengen, Good if Schengen Good Arrivals decant into departure gate, though risk of bus to baggage hall.
EDI: Excellent Excellent if domestic, otherwise Reasonable to Poor Reasonable to Poor Arrivals decant into departure hall normally, risk of bus to baggage hall.
EGC: Impractical. Bergerac has its own check-in system and is currently not on App/OLCI, so boarding passes must be obtained in person, no later than 45 minutes before departure.
FCO: Reasonable (return shuttle to main terminal) Reasonable Reasonable
FDH: Impractical due to delays during ski season - see here.
FLR: Poor due to use of bus transfers and airport layout Poor - no transfer track Reasonable
FNC: Reasonable due to small airport and long turnarounds. You do need to go landside and return to airside. Note high risk of weather related diversions. Bus from aircraft, passports, security, passports, walk to aircraft.
FRA: Reasonable to Poor Poor (particularly if coming off Schengen) Reasonable
FSC: Uncertain - if boarding passes can be issued in advance then it will be an easy landside transfer in a tiny airport. If boarding passes can only be collected in FSC then it's impossible.
FUE: Reasonable if out of the peak season, airbridges used. Have to go via passports landside and security, behind check in. Try Canaries+Families security if desperate.
GIB: Good Good Good Must go landside, bearing right and back up through security. Turnaround can be long. Leave the aircraft early so as to beat the queue at passport arrivals.
GLA: Excellent Excellent if domestic, otherwise Reasonable Reasonable Arrivals decant into departure hall normally.
GNB: Good Good Good: Walk to/from aircraft. Must go landside, outside and right back into departures. Long turnaround times make this feasible though Saturdays busy.
GOA: Reasonable Reasonable Reasonable
GOT: Excellent Excellent Excellent Borderline foolproof. Arrivals decant into departure hall.
GVA: Excellent Good Good (but can be poor during ski season) Turn left in arrival lane to go back up to departures area.
HAJ: Excellent Excellent if non-Schengen, Good if Schengen Good Arrivals decant into departure gate. See posts 1670 and 1671 below.
HAM: Excellent Excellent if non-Schengen, Good if Schengen Reasonable Arrivals decant into departure hall, though sometimes bus to baggage hall.
HEL: Good Good Reasonable Incoming passengers can reverse direction just before Schengen passports. If a bus from gate, you will need to rush.
HER: Infeasible. There is no online or App check in, it's a bus transfer and arrivals / departures are in separate buildings.
INN: Good Good Good - you have to go landside, and there is a bus transfer to/from the aircraft, but the airport is very small and highly efficient.
INV: Good to Excellent Good Good - you have to go landside and through security. See here for more info.
IOM: Good Good Good (no flight connections but small airport)
IST: Good (visa not required) Good Poor (also note you may need to buy a visa as a result of going landside). More details in this post.
JER: Excellent Excellent if domestic, otherwise Good Good Arrivals decant into departure hall, sometimes you need to double back to the BA lounge.
JMK: Nearly impossible due to clunky arrival processing and use of buses.
JTR: Impossible: bus transfer, slow passports.
KEF: Excellent Excellent if non Schengen, Good otherwise Good BA flights tip arriving passengers into the departure gate. Foolproof. NB LCY flights pax use a bus from a remote stand, still easy as dropped off less than 100M from the departure gate.
KLX: Moderately risky due to boarding passes only being issued at check-in. No buses used normally, walk off plane straight into very small building.
LBA: Good Good Good have to go landside for any connection or b2b but small airport, see here for further details
LCA: Good Good Reasonable There is a "Connecting Flights" channel on the left of the arrivals corridor, half way along, well before passports.
LEI: Moderate to risky: you have to go via landside, and you need the return boarding pass before travel. But it's a small and efficient airport. No buses are used, it's similar to LCY in operation.
LHR T3: Good Good Reasonable Follow connecting flights route, which can be as quick as 11 mins from disembark to through security. No conformance unlike T5.
see here.
LIG: Good to Excellent Good Reasonable See this post for more information
LIS: Good Good Reasonable There is a security check to the right, immediately before and avoiding the passport desks. Risk of bus gates, but still OK.
LIN: Good Good Reasonable to Poor (bus gates)
LPA: Possibly OK if off peak. Some flights are bus gates, but it's a relatively small and efficient airport. OLCI and App check in both work.
LUX: Very Good Good Good Borderline excellent, no known fatalities. Landside route is described here: Airside transfer door described here.
MAD: Very good Good to Reasonable depending on arriving terminal Reasonable See this post for full details.
MAH: Good to excellent, see post number 563.
MAN: Reasonable to Poor Reasonable to Poor Reasonable to Poor
MCT: Excellent - direct transfer route [ ] [ ].
MJV: Good Good Good provided you avoid a peak time More information here.
MLA: Good Good Good This this post and linked blog for details.
MRS: Good Good Good There is a transfer and security point just before going down to passports. Use the phone on the post to ask for it to be opened it for you; however, there is no guarantee that it will and you may have to exit to landside and re-enter through departures security.
MUC: Very good Good but note 2 terminals Good Transfer point after passport, details in this post
MXP: Good - bit of walk to Transfer facility Good Good Thread links here.
NCE: Reasonable Poor Good [There is a direct transfer route by turning into the door way on the right before the slope up to passports]
NCL: Excellent Excellent if domestic, otherwise Good Good Arrivals decant into departure hall.
NTE: Good Good Good see this post.
NUE: Impractical unfortunately due to no OLCI, all check in done at the airport
OLB: Excellent Excellent Excellent Arriving into Olbia is via jetty to the departure gate, no passports or security. Note no OLCI via the App, more info here.
ORK: Good, do need to clear passports and security but very small and efficient airport.
ORY: No recommended due to fast turnarounds on LCY services. You have to go fully landside and back in again, via 2 passport checks and a security check.
OPO: Excellent [Look for grey escalator going up] Good (reasonable if Schengen) Reasonable
OTP: Excellent as at April 2019. Poor as of 29 Dec 18, see post #2660 https://www.flyertalk.com/forum/30586858-post2660.html.
Excellent - See post #1919 https://www.flyertalk.com/forum/29017017-post1919.htmlGood - look for Connection facility on right after leaving aircraft Reasonable Poor (can be Good if all everything works)
OSL: Good on the whole Reasonable Reasonable (See experiences in this post, this post, this post and this post.)
OVD: Not really suitable. This is really an Iberia Express route but leaves T5 under BA code. The aircraft is based in OVD not LHR. Small efficient airport though.
PFO: Good on the whole, but you do need to go landside. However it is a small airport. May not be so good on a busy Saturday during school holidays. Note bus transfers however.
PMO: Airport is currently being rebuilt. Once completed potentially a good option due to airbridge. Departure security is two floors above arrivals (use lift)
PMI: Excellent Excellent Excellent borderline foolproof - you are landed direct into boarding area.
PRG: Excellent ?? ?? For back-to-back the LHR-PRG arrival dumps you right into the main corridor of that pier; walk 100 ft. to security check for the BA boarding lounge and you'll be good to go.
PSA: Reasonable Reasonable Reasonable (not the best location since there are a lot of LCC and you have to reclear security from landside). (August 2018 review and comment)
PUY: Unrealistic, due to the bus transfer process followed by passport control.
RAK: Terrible Unknown See post #1353 below
RHO: Infeasible - no OLCI or App check in, bus transfers from gates. Also airport very busy on Saturday PM and Sunday AM.
RTM: Good Good Good (Reasonable during morning/evening peaks)
SEZ: Excellent, use the Transit desk at the right side of the immigration hall, opposite end to passport control, see this post.
SKG: Reasonable Reasonable Reasonable but note bus transfers on apron.
SOF: Excellent Excellent Reasonable arrivals decant into departure area.
SPU: Reasonable but there is a bus transfer and then landside Reasonable but transfer routes seems to be from Star Alliance Reasonable
STR: Reasonable - stairs from baggage hall back to security. Can't avoid security/passports Reasonable Reasonable Report here.
SVG: Excellent Excellent Excellent borderline foolproof, though only restricted number of flights
SVQ: Reasonable but need to exit landside and go up through departures, security. and passports is by the gate. Compact airport, fast security even if queuing.
SZG: Reasonable Reasonable Reasonable no transfer channel and note bus transfers, but small airport.
TFS: Reasonable but in all cases involves going landside. May be tricky to reclear security in peak holiday season.
TIA: Probably impractical. There is a bus transfer process and passport checks/stamps takes a while (Albania isn't in the EU).
TLL: Very good Good Reasonable see this post.
TLV: At your own risk. There is a transfer route with security on the way to passport control just after the rotunda.
TNG: No transfer or B2B route. Have to pass immigration, customs and security again. Airport is tiny (think 10 flights a day) and B2B is perfectly doable provided no problems at immigration.
TRN: Reasonable to Good Good Reasonable No short cuts to avoid going landside via passports x2 and security, apart from Fast Track security, but a small and efficient airport.
TXL: Good - security takes place in limited area by arriving gate Good Good Security is at gates, if using A gates. NB: Currently, this usually includes LCY flights, which now mostly use A gates like LHR flights.
UIP: Good - very small airport, tarmac walk.
VCE: Very good Good at offpeak times Reasonable See this post for details
VIE: Excellent (BEWARE see: https://www.flyertalk.com/forum/29579878-post2190.html ) Good Reasonable
VLC: Good Good Reasonable there's no transfer route so you have to go via landside. Departures is straight up from the arrival point. Disagree with the previous two sentences. For me, a direct turnaround from gates 12-14 was possible without going landside. Took less than a minute.
VNO: Excellent Good Reasonable arriving passengers enter departing passenger area. [BA have codeshare and also has TP Run options via AY]
VRN: Good Good Reasonable there's no transfer route so you have to go landside but it's a very small airport and there is Fast Track.
WAW: Good - small connection facility on left after airbridge Good Reasonable
ZAG: Very good Good Reasonable ask to use the International Transfer channel on the left side of the passport hall, you need a boarding pass/App. NOTE: New terminal just opened, so this info needs updating.
ZRH: Generally good but see this post and the replies for more information.
ZTH: Infeasible due to buses and no online check-in possibilities. Somewhat unfortunate given the small airport. No transfer route, you must enter Schengen and go to landside.

Excellent generally means you will leave the aircraft and find yourself in the boarding area for departure. Good suggests that you may have to clear either security and / or passports before reboarding, but it should still be possible.

Two caveats:
A) Sometimes things don't go to plan. E.g. EDI sometimes uses buses, which puts passengers landside and thus needing to reclear security. Ditto HAM.
B) The above needs to be combined with the turnaround time. MXP often has a generous back-to-back time, for example.

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