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HMRC internal manual

Partnership Manual

Trading profits: notional trade and basis periods

Partners must self assess their share of the partnership’s trading profits or losses. For basis period purposes, each partner’s share is treated as profits or losses of a separate ‘notional trade’ carried on by the partner alone. Where similar activities are carried on by a partnership and by a person who is a member of that partnership on his own account, there are two trades being carried on, one by the partnership and one by the partner.

The current year basis period rules apply to each partner’s notional trade as they would to a business being carried on by a sole trader. Detailed guidance can be found at BIM81000 onwards.