What is Pre-registration VAT?
HMRC allows VAT paid on purchases made before VAT registration to be claimed under certain conditions:
The purchase was either for goods (Eg stock or equipment) the business still holds on the date of VAT registration up to 4 years prior to registration; or for services purchased in the 6 months prior to registration.
The company holds a valid VAT record for the purchase (see - https://co-accounting.co.uk/qanda/valid-vat-record).
The purchase was made for the supplies the business intends to make under its VAT registration (ie the purchases were part of the same trade).
The purchase was made by the VAT registered business. For a Ltd Company this means nothing can be claimed before its date of incorporation.
For a claim to be made all conditions must be met. The claim can only be made in the first VAT return.
For more detail visit: https://www.gov.uk/hmrc-internal-manuals/vat-input-tax/vit32000