I would go by the UK size listed in their website. The suggested TTS may not be accurate. Islay is in the 365 last and is roomier. I am a 6.5E UK in most CJ, EG and JLP. My Aldens plaza are 7D. The Islay I just got from Barney's was a 7D US and listed as 6UK on their site. Luckily I could try them in store. I would suggest to you try on or get 2 sizes if you could not try them in person as the other gentleman suggested.