We considered showing prices including VAT but after doing a price check with our competitors, we found they were all using prices excluding VAT. If we were to adopt a price including VAT then we would instantly look 20% more expensive, when in most cases we are actually cheaper.
A second reason is that in many cases the main customers for web hosting and domain names are commercial client that are VAT registered, so they can claim the VAT back.
All we can recommend is when doing price comparisons double check if the displayed prices include or exclude VAT.
