Would recommend checking out this thread on the subject of UK taxes:
post2393.html?hilit=taxes#p2393Posting this from the KS website: "How do taxes work on Kickstarter?
We can’t give tax advice, but we have compiled this guide for US-based financial professionals who may not be familiar with Kickstarter. This information is not intended to be used, and cannot be used, by any taxpayer for the purpose of (1) avoiding tax-related penalties under the US Internal Revenue Code or (2) promoting, marketing, or recommending to another party any tax-related matters. This information is just a start.
In general, in the US, funds raised on Kickstarter are considered income.
In general, a creator can offset the income from their Kickstarter project with deductible expenses that are related to the project and accounted for in the same tax year. For example, if a creator receives $1,000 in funding and spends $1,000 on their project in the same tax year, then their expenses could fully offset their Kickstarter funding for federal income tax purposes. If a creator receives funding in one year and spends money on their project in a later year, consider whether their expenses can still offset their Kickstarter funding using the accrual method of accounting.
Beyond deductions, a creator may be able to classify certain funds raised on Kickstarter as a nontaxable gift, and not income. A gift is something given out of “detached and disinterested generosity” for personal reasons and without the expectation of getting something in return.
Sales tax may also be applicable in certain cases depending on the local rules. In general, sales tax applies only if the creator has sufficient connection to the location of the backer.
For project creators outside the US, please refer to your local tax authorities:
United Kingdom:
http://www.hmrc.gov.uk Canada:
http://www.cra-arc.gc.ca Australia:
http://www.ato.gov.au New Zealand:
http://www.ird.govt.nz"
USA does not have VAT to my knowledge.
You may want to think about where you expect your backers to come from. If you are in the UK and you think your backers will come from the US, they will have to pay an exchange rate, which may deter some pledges.