VAT and different companies

I am registered as self employed and am a sole trader. I am going to keep my sales below the VAT threshold (sell wedding stationery). A friend has approached me regarding setting up a company together and creating a webstore selling DIY wedding stationery elements. Should this go over the VAT threshold, which we'd expect, would that affect my other business?

Provided it is a seperate company you shoul have no issues.

Your self employed business and company are two seperate persons/entities for VAT purposes.

If the 2 businesses are closely related in the activities that they do, you will be caught by Revenues anti fragmentation rules which prevent people splitting businesses into different vehicles ie a company and sole trader and keeping one or both under the VAT registrations limit.
I think that as the business are similiar in this case you would have to register.