Interesting. Would you choose "three July twenty fifteen", "July third twenty fifteen", or "the third of July twenty fifteen" (substitute "two thousand" for "twenty" if you like)? Assume someone has asked you the date and you're responding out loud.
It took me a while to figure this out because actually it's quite rare to speak a date including a year without reading it - most spontaneously-spoken dates are this year (so the year is implied) and for a read dates, I'd probably say whatever was written.
The clincher was how I'd say my birth date, which would be of the form above.
I'm not claiming to be the definitive British English speaker, though! ;)
...and as another poster commented, it might depend on context - for example, "September 11" is often used in British English because it refers to an American event.