Qualifying income under SI 2026/336 regulation 25 (which replaced SI 2021/1076 regulation 20 on 1 April 2026 when the new Income Tax (Digital Obligations) Regulations 2026 revoked the prior 2021 Regulations) is gross self-employment turnover plus gross property rental income, before deductions, aggregated across the two streams in the test year. The threshold figures (£50,000 from 6 April 2026, £30,000 from 6 April 2027, £20,000 from 6 April 2028) are gross figures, not net profits. A landlord with £52,000 gross rental income and £40,000 of allowable deductions (£12,000 net profit) is in scope at the April 2026 mandate; the intuitive net-profit-based test produces the wrong answer. The aggregation rule combines self-employment and rental streams: £30,000 of trade plus £25,000 of rental equals £55,000 combined and pulls a landlord-trader into scope at April 2026. Excluded from qualifying income: employment income (PAYE), pensions, dividends, savings interest, partnership profit shares (until the deferred partnership phase commences), limited company rental (the company's CT-side income), and pension fund (SIPP / SSAS) rental (the scheme's income). The letting-agent net-of-fees trap: a landlord must test against gross rent collected by the agent, not the net paid to the landlord after agent commission and management fees. Joint-property treatment: each owner tests their share of gross (default 50/50, or per the Form 17 election where filed).