VAT added depending on Attributes selected

[JaminT]

What country are you located in?

If United Kingdom, and you are selling to the public, all your prices must be displayed with vat INCLUDED. That is the law (UK Price Marking Order 2004).

Thank you for your reply.

Yes i am in the UK.

What i am trying to say is that i am trying to set up a single product on the website for which some of the sizes (attribute options) include VAT and others are VAT exempt.

So a pair of shoes for instance might be £24.00 for sizes 2-5 (tax exempt) but sizes 6-11 are £28.80 as they include VAT.

We would like to make it so that if a customer selects a size 4 they are not charged VAT but with a size 8 they have VAT added.

Thanks,