NY expressed precisely :
I remember once being stopped by the police for some minor offence - maybe a
brake light bulb that had failed - and being asked my address which I gave
them, spelling out the postcode phonetically. The police officer looked as if
he thought I was taking the **** by using "the police's" phonetic alphabet to
him ;-)

I always use phonetics when for my email, postcode, name and address,
when its important to get it absolutely correct.