As anyone who’s ever travelled on separate tickets before will know, an interline agreement can make all the difference between a smooth connection, and a stressful rush.ย ย
The convenience of getting all your boarding passes at one shot and checking your bag through to the final destination should not be understated, especially if your inbound flight arrives late or if a terminal change is required.
In this post, we’ll look at what interlining is, and the agreements that Singapore Airlines has in place.ย
What is interlining?
While there’s probably a more technically correct definition, I prefer to think of interlining simply as an agreement that allows Airline A to send passengers onto Airline B, without requiring them to reclaim their luggage or check-in again.
Interlining is important when dealing with flight disruptions (since an airline typically rebooks passengers onto another airline it interlines with), but is more commonly encountered when dealing with two separate tickets.
Depending on your situation, the presence of an interline agreement can either be a mild convenience, or absolute necessity.ย
For example, I might redeem a Qatar Airways ticket from KUL-DOH-MXP, and then purchase a separate Singapore Airlines ticket from SIN-KUL. Since Qatar Airways and Singapore Airlines interline, I could get my boarding passes in SIN and check my bag all the way through to MXP, saving me the time of clearing arrival immigration in KUL, claiming my bag, checking in and clearing departure immigration again.ย
However, an interline agreement may very well determine the underlying viability of a journey in the first place. If I want to fly from A > B > C, but cannot enter Country B without a visa (and don’t intend to apply for one), then I’m counting on being able to check my bag all the way through from A to C.
I’ll talk about some caveats to interlining later in this article, but first, let’s look at the agreements that Singapore Airlines has.
Singapore Airlines’ interline agreements
At the time of writing, Singapore Airlines has interline agreements with more than 100 carriers worldwide.
The information below is extracted from the KVS Tool (a paid subscription is required to use it).ย
[KVS Tool 10.4.1 – Reference: Interline Agreements [IET]: SQ]
ELECTRONIC INTERLINE CARRIER AGREEMENTS-SQ INTERLINE CARRIER CODES AA – AC – AD – AE – AF – AH – AI – AM – AS – AT- AV – AY – AZ – A3 – BA – BG – BI – BP – BR – BT – B6 – B7 – CA – CI – CM – CX – CZ – DJ – DL – EI -EK – EN – ET – EW – EY – FI – FJ – FM – FZ – GA- GF – G3 – HA – HM – HO – HR – HU – HX – HY – IB- IC – IY – JJ – JL – JO – JU – KC – KE – KF – KL- KM – KQ – KU – LA – LG – LH – LM – LO – LP – LR- LX – LY – ME – MF – MH – MI – MK – MS – MU – NF- NH – NX – NZ – OA – OK – OM – OS – OU – OZ – O6- PD – PG – PK – PR – PS – PX – PZ – QF – QR – QV- RA – RJ – RO – SA – SB – SC – SK – SN – SQ – SU -SV – SW – S7 – TA – TG – TK – TP – TR – T0 – UA- UB – UK – UL – UX – VA – VN – VS – VY – WF – WY -W2 – XL – ZH – 4M – 4U – 4Z – 9B – 9W |
For those of you who don’t speak airline code, here’s a summary of which code refers to what airline.ย
Code | Airline |
4M | Lan Argentina |
4U | Germanwings |
4Z | Airlink |
9B | AccesRail |
9W | Jet Airways |
A3 | Aegean Airlines |
AA | American Airlines |
AC | Air Canada |
AD | Azul Linhas |
AE | Mandarin Airlines |
AF | Air France |
AH | Air Algรฉrie |
AI | Air India |
AM | Aeromexico |
AS | Alaska Airlines |
AT | Royal Air Maroc |
AV | AVIANCA |
AY | Finnair |
AZ | Alitalia |
B6 | JetBlue |
B7 | Uni Air |
BA | British Airways |
BG | Biman |
BI | Royal Brunei |
BP | Air Botswana |
BR | EVA Air |
BT | Air Baltic |
CA | Air China Limited |
CI | China Airlines |
CM | COPA Airlines |
CX | Cathay Pacific |
CZ | China Southern Airlines |
DJ | Air Djibouti |
DL | Delta Air Lines |
EI | Aer Lingus |
EK | Emirates |
EN | Air Dolomiti |
ET | Ethiopian Airlines |
EW | Eurowings |
EY | Etihad Airways |
FI | Icelandair |
FJ | Fiji Airways |
FM | Shanghai Airlines |
FZ | Flydubai |
G3 | VRG Linhas Aรฉreas S.A. – Grupo GOL |
GA | Garuda |
GF | Gulf Air |
HA | Hawaiian Airlines |
HM | Air Seychelles |
HO | Juneyao Airlines |
HR | Hahn Air |
HU | Hainan Airlines |
HX | Hong Kong Airlines |
HY | Uzbekistan Airways |
IB | IBERIA |
IC | Indian Airlines |
IY | Yemenia |
JJ | TAM Linhas Aรฉreas |
JL | Japan Airlines |
JO | Aircompany JONIKA |
JU | Air SERBIA a.d. Beograd |
KC | Air Astana |
KE | Korean Air |
KF | Blue1 |
KL | KLM |
KM | Air Malta |
KQ | Kenya Airways |
KU | Kuwait Airways |
LA | Lan Airlines |
LG | Luxair |
LH | Lufthansa |
LM | Loganair |
LO | LOT Polish Airlines |
LP | Lan Perรบ |
LR | LACSA |
LX | SWISS |
LY | EL AL |
ME | MEA |
MF | Xiamen Airlines |
MH | Malaysia Airlines |
MI | Silkair |
MK | Air Mauritius |
MS | Egyptair |
MU | China Eastern |
NF | Air Vanuatu |
NH | All Nippon Airways |
NX | Air Macau |
NZ | Air New Zealand |
O6 | Avianca Brasil |
OA | Olympic Air |
OK | Czech Airlines j.s.c |
OM | MIAT |
OS | Austrian |
OU | Croatia Airlines |
OZ | Asiana |
PD | Porter Airlines |
PG | Bangkok Air |
PK | PIA |
PR | PAL |
PS | Ukraine International Airlines |
PX | Air Niugini |
PZ | TAM – Transportes Aรฉreos del Mercosur Sociedad Anรณnima |
QF | Qantas |
QR | Qatar Airways |
QV | Lao Airlines |
RA | Nepal Airlines |
RJ | Royal Jordanian |
RO | TAROM |
S7 | Siberia Airlines |
SA | SAA |
SB | Aircalin |
SC | Shandong Airlines |
SK | SAS |
SN | Brussels Airlines |
SQ | SIA |
SU | Aeroflot |
SV | Saudi Arabian Airlines |
SW | Air Namibia |
T0 | TACA Peru |
TA | TACA |
TG | Thai Airways International |
TK | THY – Turkish Airlines |
TP | TAP Portugal |
TR | Scoot |
UA | United Airlines |
UB | Myanmar National Airlines |
UK | Vistara |
UL | SriLankan |
UX | Air Europa |
VA | Virgin Australia |
VN | Vietnam Airlines |
VS | Virgin Atlantic |
VY | vueling |
W2 | FlexFlight |
WF | Wideroe |
WY | Oman Air |
XL | LanEcuador |
ZH | Shenzhen Airlines |
Note that the system has some “leftovers”, such as Germanwings (since rebranded to Eurowings with a different airline code) and Indian Airlines (folded into Air India in 2011).
Caveats about interlining
Interlining on separate tickets is not a given
Interlining agreements are primarily concerned with facilitating the travel of passengers across different airlines on the same ticket.ย Just because two airlines have an interline agreement does not mean they’re obligated to check you through when travelling on separate tickets.ย
Most of the time they should, but keep in mind this is done as a courtesy, as Cathay Pacific puts it:ย
As a courtesy, Cathay Pacific will through-check you and your bags to your final destination if you are travelling on separate tickets involving connections with our interline partners. However through-check may not be possible on their return journey if your travel begins with an airline that does not to provide separate ticket through-check service.
Still, you may encounter the odd agent who is unfamiliar with the rules or unwilling to assist. I’ve been in situations where agents refused to check my bag through on the grounds that the second airline was not part of the same alliance, notwithstanding the fact an interline agreement existed.
It pays to be patient, polite, and know your stuff. MileLion community member Ray suggests a trick that can work if both airlines are on the Amadeus system, namely asking the agent to enter TGAD-XX where XX is the airline’s code. This displays a full list of interline agreements.ย Alternatively, entering TGAD-XX/YY will display the interline agreement between the validating carrier XX and the second carrier YY.ย
All the same, there’s alwaysย some degree of risk in booking separate tickets, especially if you have luggage.ย
Interlining must respect MCT
If you’re booking two separate tickets, you should make sure the Minimum Connecting Time (MCT) is satisfied.
As the name suggests, MCT is the minimum time between the scheduled arrival of one flight and the scheduled departure of another. Bangkok, for example, has the following MCTs:
- Domestic to Domestic: 1h 15 mins
- Domestic to International: 1h 15 mins
- International to Domestic: 1h 15 mins
- International to International: 1h 15 mins
This means that if you book a separate SIN-BKK and BKK-KIX ticket and the arrival of the first flight is within 1h 15 mins from the departure time of the second flight, your request to interline will be denied.
Regular customs rules still apply
Interline agreements are still subject to the standard customs restrictions.
For example, Singapore Airlines and JetBlue have an interline agreement, but US laws require passengers to collect their bags and clear customs at their first port of entry. So if you had a Singapore Airlines SIN-SFO and a JetBlue SFO-BOS ticket, you would still need to collect your bag in SFO and clear customs before sending it off again on the SFO-BOS leg.ย
Similar rules apply to Australia and New Zealand, where your connecting flight is a domestic one.ย
Conclusion
Interlining agreements are very important to miles collectors who intend to book separate tickets across two different frequent flyer programmes. While interlining on separate tickets is never guaranteed, it can be done more often than not.
I would, however, ensure that I had a backup plan for a worst case scenario where the agent at the first airport is unwilling or unable to check the bag through.ย
Be also careful with immigration/visa requirements at the connecting point between separate tickets. E.g. Qatar Airways has this condition on every e-ticket, and theyโre not the only airline that enforces this: โข Remember to check your immigration and health requirements before you travel and ensure you carry the required travel documents. โข If you are holding a non-Qatar Airways ticket for a connection afterwards, you will need to hold immigration approval to land at the final city in your itinerary that is ticketed by Qatar Airways SQ seems to be more relaxed on that. I connected recently in DEL between… Read more »
“Most of the time they should, but keep in mind this is done as a courtesy,” I find this statement not a very good one. You give the impression that all airlines should do it, it’s just a matter of competence of the check in staff whether it’s done or not. This is not true, many airlines have long standing policies of rejecting any through check-in in almost any circumstances unless the entire itinerary was on a single ticket (ie they will only check in for the end destination on the ticket they are responsible for, and not for any… Read more »
The simplest solution to all the complexity is to just fly without check-in luggage. So we have a SIN-IST award ticket (IST being the “sweet-spot”). It is business so we can carry on what we need. No check-in. Then, we have a ticket on TK leaving IST about 5 hours later to a European city. So this whole interline topic becomes irrelevant. We online check-in for the TK flight ex-IST and print our boarding passes. We check-in, in SIN and collect out boarding passes to IST. We don’t even need to tell SQ about the second flight! When arriving in… Read more »
Pointless. As soon as your A-B leg gets delayed, causing you to miss the B-C leg, the second airline does not extend the “courtesy” to get you on the next available flight. As far as the second airline is concerned, you should’ve been located in the city.
So this hack is not useful at all, even if you take carry-on only. Better to book a single ticket.
Thanks for the info, just in time for my flight from EWR to SIN next month. Though it makes me nervous, because we have an incoming flight into EWR on UA on a separate ticket, and I’ve heard UA agents can be quite indifferent with interline agreements with separate tickets.
Most recently I had separate tickets on Avianca and Turkish from Bogota to Istanbul connecting in Madrid. Both AV and TK are both Star Alliance and I had 5 hours of connecting time. The AV flight even had a TK codeshare and they STILL insisted they couldnโt interline because of separate tickets ๐
I was flying in JL J class NRT-KUL using the now defunct Alaska Airlines redemption stopover trick and bought a separate onward Y class KUL-SIN on MH, hoping that as OneWorld partners, they would interline.
No such luck. The ticketing agent refused to check me and my baggage through. Fortunately I had factored a 4-hour connection but it’s still a pain having to retrieve the luggage and going through immigration and check-in again.
A small price to pay for an ultra-cheap business class return ticket though.
I had the exact same itinerary as you when travelled in 2019. The JAL agent able to check through my luggage to SIN when I told her I had a connecting MH flight at KUL.
Not for boarding pass. I need to go to the transit counter at KUL to have it print out. Maybe the JAL agent misunderstood you. You should ask for only luggage to check through and not your connecting boarding ticket too.
so.. SQ has an interline agreement with… SQ???
Singapore is my neighboring country. But I have never traveled.
I plan after the covid 19 epidemic is better I will travel for a couple of days.
My personal experience :
looks like our home airport does better at the interlining.
SA – I had earlier got SQ CSO to link” my 2 separate reservations, do you think I will get the same experience with your SAS?
Where is this information from? I just called Singapore airlines to confirm and your information is incorrect. This could cause a lot of troubles for people and you should check it before publishing incorrect information!
Hello,
Has anyone successfully interline Thai Airways to Singapore Airlines ?
I suspect as they are both star alliance that it should be easier ?
However my journey will start in Sapporo so not sure how staff counter will react.
Round Trip : Sin-Bkk-Cts & Cts-Bkk-Sin
Thanks
interlining on separate tickets is never guaranteed, but since they’re both *A carriers your odds should be pretty good
This had sort of put my mind at ease. As a solo traveler going to Australia and Bali at end of year I was very concerned about through check in. I booked my entire journey direct with Singapore Airlines. But I seem to have had different information from different people, some say I can through check in but same say I canโt. I fly with KLM from Glasgow, Scotland to Amsterdam, change onto Singapore airlines then eventually Sydney. So i believe if I ask nicely I can get through check in. I was told because my layover is less than… Read more »