Forms covered
| Form | Description |
|---|---|
| CIS304 | CIS partnership registration (subcontractor): registers a partnership as a subcontractor and sets its tax treatment |
| SA800 | Partnership Tax Return 2026: reports partnership income, expenses and disposals, and allocates profit to partners |
| SA104F | Partnership (full) 2026: a partner’s share of profits and other income |
| SA104S | Partnership (short) 2026: a partner’s share of simple trading profit or loss |
CIS304 registration
- Register before starting work as a subcontractor.
- Registered subcontractors face 20% deductions, unregistered 30%.
- The partnership and registering partner must both have a UTR and be registered for Self Assessment.
- Gross payment status requires passing business, turnover and compliance tests.
SA800 partnership return
- The partnership isn’t taxed itself: the Partnership Statement divides profit among partners.
- The nominated partner files it for all partners.
- For 2026-27, due 31 October 2027 on paper or 31 January 2028 online.
- Turnover below £90,000 uses the short summary; £90,000 to £15 million uses the detailed page.
SA104F and SA104S
Use SA104S for a simple profit share. Use SA104F for untaxed foreign or property income or other complications. Copy figures from the matching boxes in the Partnership Statement.
FAQs
Frequently asked questions
Does the partnership pay tax on its profits?
No. Each partner reports their share on their personal return.
When should a partnership register under CIS?
Before starting work as a subcontractor, using form CIS304.
What is the SA800 deadline for 2026-27?
31 October 2027 on paper or 31 January 2028 online.