例子，去掉除了贷款利息之外的所有费用收入4000，贷款利息2000，看看交多少税。
对最高税率20%的人，需要交的税，4000x20% - 2000x20% = 400, This is for ever，新政不影响。
对最高税率40%的人，需要交的税。
新政以前, 4000x40% - 2000x40% = 800
2016, 4000x40% - 1500x40% - 500x20% = 900
2017, 4000x40% - 1000x40% - 1000x20% = 1000
2018, 4000x40% - 500x40% - 1500x20% = 1100
2019, 4000x40% - 2000x20% = 1200
…
最高税率45%的人，把上面计算公式里面的40%换成45%就行。
Landlords will be able to obtain relief as follows:
in 2017-18 the deduction from property income (as is currently allowed) will be restricted to 75% of finance costs, with remaining 25% available as a basic rate tax reduction;
in 2018-19, 50% finance costs deduction and 50% given as a basic rate tax reduction;
in 2019-20, 25% finance costs deduction and 75% given as a basic rate tax reduction; and
from 2020-21, and beyond, all financing costs incurred by a landlord will be given as a basic rate tax reduction.
In effect, deductions from property income will be restricted to:
75% for 2017-18;
50% for 2018-19;
25% for 2019-20;
0% for 2020-21 and beyond.
Individuals will be able to claim a basic rate tax reduction from their income tax liability on the portion of finance costs not deducted in calculating the profit.
Accoriding to HMRC guidance, in practice this tax reduction will be calculated as 20% of the lower of the following:
finance costs not deducted from income in the tax year (25% for 2017-18, 50% for 2018-19, 75% for 2019-20 and 100% thereafter);
profits of the property business in the tax year;
total income (excluding savings income and dividend income) that exceeds the personal allowance and blind person’s allowance in the tax year.
Any excess finance costs may be carried forward to following years if the tax reduction has been limited to 20% of the profits of the property business in the tax year.
