Research and development (R&D) tax credits can only be claimed by companies which are liable to UK Corporation Tax. Limited Liability Partnerships (LLPs) do not pay UK Corporation Tax and as a result they usually cannot claim R&D tax credits.
R&D tax credits are a form of Corporation Tax relief and so, as a limited liability partnership (LLP), you cannot usually claim as you are not registered for UK corporation tax.
When LLPs can qualify for R&D tax credits
If your partnership has a corporate partner, that corporate partner will be subject to Corporation Tax on its share of profits from the partnership. You therefore may be able to benefit from R&D tax credits for R&D activities carried out by the partnership, in proportion to your partner profit-share.