Personal taxation · Luxembourg
Luxembourg tax return examples: assumptions and limits
These examples are fictitious and for teaching purposes. They show how to distinguish a deduction from the taxable base, a rental result and an effect on the tax scale. Each result rests on explicit assumptions; no case promises the same treatment for a real file.
Financial Services Luxembourg · Licensed accountant · Head of the firm: Mickaël LOC. Editorial update: .
Three fictional calculations: tax year 2025
Eligibility assumptions are taken as verified. These examples do not describe any client of the firm.
1. Effect limited to the tax scale, class 1
Base before reduction: EUR 60,000. Additional reduction allowed: EUR 3,000. Scale before: €11,945.00; after: €10,693.00; difference: €1,252.00. Excluding tax credits, tax treaties and refunds.
2. Result of a let property
12,000 − 2,000 − 1,500 − 1,000 = €7,500.00. For a 50% ownership share: €3,750.00. This is net income, not tax.
3. Main home mortgage interest
Available since 2023, two ceiling units allowed. Interest EUR 9,500 − subsidy EUR 500 = €9,000.00. Ceiling: €8,000.00. Amount retained: €8,000.00, to be included in the file under the applicable rules.
Base reduction: comparing two tax amounts
The first example uses a 2025 adjusted taxable base that has already been determined and an additional reduction assumed to be allowable. It does not assess whether an insurance policy, a donation or a contract is eligible.
The difference shown concerns only the tax scale for the tax classes covered, without personal credits, extraordinary income or tax treaties. A refund would require other data.
Rental: the result is not the tax
The second example calculates the result of a property from expenses that have already been classified and then applies a share. Accounting for the monthly loan instalments does not replace this statement.
The location and the regime of the property are decisive assumptions. The rules for a property abroad or a professional operation cannot be inferred from this example.
Home: the ceiling is not the saving
The third example distinguishes gross interest, subsidy and a ceiling multiplied by the eligible units. It shows the amount taken into account under these assumptions, not the final tax benefit.
The year in which the home became available for occupation and the household's eligibility are assumed to have been checked. They are not established by the calculation.
From a teaching case to your file
The documents and the classification must come before any transposition. A difference in residence, regime or year may change the result. The firm defines an engagement before handling real documents.
None of these cases is presented as an engagement actually carried out, as proof of a result or as a testimonial. The tools keep their own scope and limits.
The firm’s other tax engagements
Depending on your situation, the firm also handles tax, VAT and payroll, the regularisation of late tax filings and assistance during a tax audit. Fees are listed in the firm’s fee grid.
Official sources and scope
- ACD: tax scales and official calculation
- ACD: privately owned property let out
- ACD: own home and deductible interest
The rules apply to the year and profile concerned. Examples flagged as fictitious explain a method; they are not an individual validation. The documents and options of your file are covered by a separate engagement.