Thomas sez, "Thought United Airlines covered every possible title? Not a chance. British Airways covers absolutely everything including — I kid you not — 'His Holiness' and 'Her Majesty'. Because I'm sure the Pope needs air miles."
Mr
Mrs
Ms
Miss
Dr
Herr
Monsieur
Hr
Frau
A V M
Admiraal
Admiral
Air Cdre
Air Commodore
Air Marshal
Air Vice Marshal
Alderman
Alhaji
Ambassador
Baron
Barones
Brig
Brig Gen
Brig General
Brigadier
Brigadier General
Brother
Canon
Capt
Captain
Cardinal
Cdr
Chief
Cik
Cmdr
Col
Col Dr
Colonel
Commandant
Commander
Commissioner
Commodore
Comte
Comtessa
Congressman
Conseiller
Consul
Conte
Contessa
Corporal
Councillor
Count
Countess
Crown Prince
Crown Princess
Dame
Datin
Dato
Datuk
Datuk Seri
Deacon
Deaconess
Dean
Dhr
Dipl Ing
Doctor
Dott
Dott sa
Dr
Dr Ing
Dra
Drs
Embajador
Embajadora
En
Encik
Eng
Eur Ing
Exma Sra
Exmo Sr
F O
Father
First Lieutient
First Officer
Flt Lieut
Flying Officer
Fr
Frau
Fraulein
Fru
Gen
Generaal
General
Governor
Graaf
Gravin
Group Captain
Grp Capt
H E Dr
H H
H M
H R H
Hajah
Haji
Hajim
Her Highness
Her Majesty
Herr
High Chief
His Highness
His Holiness
His Majesty
Hon
Hr
Hra
Ing
Ir
Jonkheer
Judge
Justice
Khun Ying
Kolonel
Lady
Lcda
Lic
Lieut
Lieut Cdr
Lieut Col
Lieut Gen
Lord
M
M L
M R
Madame
Mademoiselle
Maj Gen
Major
Master
Mevrouw
Miss
Mlle
Mme
Monsieur
Monsignor
Mr
Mrs
Ms
Mstr
Nti
Pastor
President
Prince
Princess
Princesse
Prinses
Prof
Prof Dr
Prof Sir
Professor
Puan
Puan Sri
Rabbi
Rear Admiral
Rev
Rev Canon
Rev Dr
Rev Mother
Reverend
Rva
Senator
Sergeant
Sheikh
Sheikha
Sig
Sig na
Sig ra
Sir
Sister
Sqn Ldr
Sr
Sr D
Sra
Srta
Sultan
Tan Sri
Tan Sri Dato
Tengku
Teuku
Than Puying
The Hon Dr
The Hon Justice
The Hon Miss
The Hon Mr
The Hon Mrs
The Hon Ms
The Hon Sir
The Very Rev
Toh Puan
Tun
Vice Admiral
Viscount
Viscountess
Wg Cdr
(Thanks, Thomas!)
Update: Johannes points out a glaring omission here: in German, someone with multiple PhDs goes by Doktor Doktor Doktor (und zo weiter), abbreviated DDDDr — how does BA expect to attract hyper-educated Germanic people without this honorific in its otherwise exhaustive list?