You've got to figure out the smallest limits and fit them. Sorry!
Your luggage allowance will be determined by the longest leg of your first trip i.e. KLM to Calgary i.e. 1 item of check-in baggage*, each max. 23 kg (50.5 lbs), max. 158 cm (62 inches) l + w + h
This of course depends on class of travel and your frequent flyer status.
This entriely depends on how you have purchased your ticket? KL/DL and AF are all part of skyteam? so they may have a policy in place where your baggage is the same all the way through, it will be on your ticket, if you ring the airline they will be able to clarify.
I believe that for every flight that originates in or ends in the US, the rules of the carrier from which you purchased your ticket applies to all segments. That would be KLM in your case. You might have to do some research to pull up the regulation.
Simple answer from the web-site
<< Your exact baggage allowance is always stated on your ticket, and in My Trip.>>
The KLM baggage allowance info is quite involved... have you thought of asking the actual airline?
Thanks for all the input. Not travelling till September but was just wondering whether to buy an excess baggage allowance. Will now try and call KLM but as we all know, it's not always the easiest of things trying to speak to an individual....
Okay... as of last year the law in the US changed. The baggage limits of the marketing carrier apply throughout the itineraries of travelers entering the US... so... that is likely to mean that you will escape a Delta baggage charge. But, it isn't an easy rule to understand and hasn't been communicated very well to check-in people.
Carryon rules apply based on the country you are flying out of... each segment. The most restrictive carryon will be AF/KLM.
each (new) check-in attracts a potential baggage fee.
just called delta. takes 2 minutes...Edited: 8:36 pm, August 01, 2013
In the US all domestic legs of an international flight taken with in 24 hrs get the international rate.
when I check in my bags are always checked all the way thru to my final destination.
I am flying in Oct BOI to BKK with Alaska and Korean Air I have flown this flight before and I get the international baggage rates.
I always print out the page that states that and bring it with me at check -in I did have a check-in agent one time
that was unaware and tried to charge me for baggage on a first domestic leg.
Geomedic's information is news to me (I'll have to read up on it).
As I understand it, for multi airline international trips, the checked baggage rules used are those of the "most significant carrier" (MSC) which usually - though not always - works out as the airline flying the longest leg. In your case that will be the airline flying the transatlantic portion of your UK-Calgary outbound, and your San Diego-UK return. In all likelihood that will be one free checked bag weighing up to 23kg, unless you have elite frequent flier status with the MSC in which case it would be more. And as sawadeeka says, domestic connections won't attract a fee if on the international itinerary.
If you're flying a domestic leg between Calgary and San Diego, you'd be subject to the airline's domestic requirements (and I include Canada-US flights on this) and that may well attract a bag fee.