Robert is right, there. It is usually the travel agents and airlines that will say that you need 6 months on your passport, and it is they that are creating the confusion.
You definitely don't need 6 months on your passport. It just needs to be valid for the dates of travel. We went to the US in May with only a couple of days left on our passports when we returned, and we weren't questioned once. The only comment made was to remind us to renew our passports as they were due to expire. We don't have visas, either.
I hope this helps.
Nuala
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