Let me take a look at this and I'll get back to you.
I need one other piece of information from you. Do you live in Lebanon? If not, where do you live?
The fact that you apply for your rental income to be paid to you without deduction of tax at source and are successful in that application does not mean that it isn't taxable in the UK. It is taxable in the UK. You can apply to be paid gross if you think that your tax affairs are up to date, that your letting expenses will exceed the rental income or any rental profit will be covered by the personal allowance if you are entitled to one (see below).
You will be entitled to a personal allowance (currently £11,000) to use against your rental income if you meet the criteria in paragraphs 8.12 or 8.13 on page 53 HERE. You are not entitled a UK personal allowance under the UK/Kuwait tax treaty (see page 23 HERE)and there is no such treaty between the UK and Lebanon.
Take a look at Section 1 HERE for the UK tax bands.
I hope this helps but let me know if you have any further questions.
You cannot claim your regular living expenses against your UK rental income I'm afraid. You pay tax at 20% on the first £32,000 of taxable income (rental income less expenses less personal allowance if applicable).
The UK personal allowance is the amount of income an individual can receive and pay no tax on in any one tax year.
Take a look here and here for information on the types of letting expenses you can claim against rental income.
Unless you meet the criteria I gave you a link to earlier, you won't get the personal allowance.
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