We'd recommend it. It will help you to win more work.
As some of our clients are large-scale Social Housing providers, they are required to register for CIS (the Construction Industry Scheme). CIS is an HMRC scheme related to VAT payments. For certain types of work, our clients must only select CIS-verified tradesmen.
As a result, you'll get the opportunity to win more work if you're a part of the scheme.
You can read more about what CIS is, and register for it on the HMRC website: https://www.gov.uk/what-you-must-do-as-a-cis-subcontractor/how-to-register