There must be dozens of threads on this topic already, but here goes:
A UK
citizen is immediately subject to paying the local
taxes as soon as they arrive. A UK-flagged
boat may never be subject to taxation, but there are soooo many details.
Firstly, are you talking
import duties, or sales and use
taxes, or personal property taxes? A cruising
permit allows you to avoid the federal
import duties for a year. Technically you have to exit the US and return more than 15 days after expiration to renew your cruising
permit for another year (and another and another).
Canada and the
Bahamas are useful places to exit. Some people have found this requirement not enforced, others have. YMMV. If for some reason you were to have to pay import duties they are generally 1.5% of the value of the vessel plus a few small
fees. But there are any number of people here on CF who have had foreign-flagged vessels in the US for years without importing them and paying duty.
The US has 50 states, and each of those has some number of counties. For the Great Loop you will be passing through somewhere around half of those states. Each state (and even each county) has different tax rules. Visitors (from a different state or from a different nation) can generally avoid the state taxes for a period of 60 to 90 days pretty easily, just by not staying within that state for longer than the visitor's exemption period. Each state is different, so you have to learn what each state requires. Foreign-flagged vessels may be able to avoid the sales and use taxes for longer, but again, every state is different.
There are games to be played. Some states have no sales or use taxes, these are the easiest for long term
storage. Others have exemptions for
storage or
repairs while
on the hard but not if stored in the
water.
Come, visit, enjoy. Do part of the Loop. If you find you are getting to a point where you will be spending a couple of months in one location then investigate the nearest 3 or 4 states. Figure out which one is the right place for your plans.
Here's an
article, somewhat dated, that should give you the flavor of the different tax regimes along the
east coast.