Hi psymes,
If you are supplying consultancy service to a business in the UK then this should be covered by the General Rule of Services which will mean that the UK business customer will account for the VAT under the reverse charge and there will be no requirement for you to register for VAT.
For this type of service the Place of Supply is determined by where the business customer belongs and not where the supply is performed.
Please see trhe guidance below:
5. Reverse charge
Thank you.