Can I claim for freelancers and contractors expenses in relation to R&D?

You may claim for freelancers and contractors under the SME scheme. If they are not connected parties you may claim for 65% of the cost. If they are connected parties you may claim the lessor of 100% of the cost or the relevant expenditure of the contractor which itself consists of staff costs, consumable items, software, externally provided workers or the subjects of clinical trials.

For the RDEC scheme you may only claim for freelancers and contractors who are individuals, partnerships of individuals or qualifying bodies which are typically universities or hospitals.