Six lines, three of which are fixed by law and one of which is fixed by a building you do not control. Working through them in order produces a figure that survives the first annual charges reconciliation.
Line one: the acquisition cost, which cannot be borrowed
Registration and transcription duties amount to 7% of the price, being 6% registration and 1% transcription. The notary's emoluments are set by regulation and run to roughly 1% to 1.5% with VAT on top, plus disbursements and, where you borrow, the mortgage deed.
These costs are normally excluded from mortgage financing and must come from your own funds. That is the constraint that catches buyers who have assembled a deposit and not the costs.
Against the duties sits the Bëllegen Akt: a tax credit of €40,000 per buyer, €80,000 for a couple acquiring together, permanent at that level since July 2025 and applied by the notary at the deed with no separate application. A minimum of €100 in duty remains payable in all cases, and the credit is personal and lifelong, so an unused balance stays available for a future principal residence.
Two conditions: you must occupy the property as your principal residence, from entry into possession or within two years, and to combine two credits the deed must record a joint acquisition en indivision.
Line two: the mortgage, sized by rules rather than by appetite
Lending follows CSSF Regulation 20-08 of 3 December 2020. The general loan-to-value principle is 80%, applied with differentiation: first-time buyers of a principal residence can be financed up to 100% of the price, other principal-residence purchases generally to 90%, and buy-to-let at 80%.
The debt-service ratio commonly cited around 40% is banking practice rather than a legal rule, and lenders assess remaining disposable income alongside it, applying a stress test so the loan is sized against a rate materially higher than the one offered.
A 100% loan-to-value does not mean no cash is required. It refers to the price, not to the cost of acquiring.
Line three: ordinary charges, which are an estimate until they are not
The monthly figure quoted in a listing is an avance sur charges. Once a year the syndic produces the accounts, the general assembly approves them, and the difference is billed or refunded.
Ask for the reconciled accounts for two completed years, not the provision. A building that has recently replaced a lift, repointed a facade or changed its heating plant carries that in the numbers, and a low provision against high reconciled costs is a deferred bill rather than a saving.
Line four: the works fund, which is compulsory
Since 1 August 2023, under the law of 30 June 2022, every Luxembourg co-ownership must hold a fonds de travaux, funded by a compulsory annual contribution allocated in proportion to each owner's millièmes.
The amount is voted at the general assembly but cannot fall below a floor fixed by grand-ducal regulation, expressed per square metre of energy reference surface and graded by the building's thermal insulation class. The Ministry of Housing has estimated €30 to €40 a month for an 80 m² apartment in a poorly performing building.
Ask three things: the current balance, the annual contribution for this lot, and whether any works have been voted and not yet called for. That last item is an existing liability rather than a risk and should be priced at full value.
Line five: your own running costs
Energy, which depends almost entirely on the class. The gap between a class A new-build and an unrenovated class G building runs to several hundred euros a month over a heating season from roughly October to April.
Note that the supplier and the network operator are separate entities here. Creos operates the network and performs the annual meter reading on behalf of all suppliers; your supplier sells the energy. Switching supplier requires no change to the meter, and default supply is regulated but priced above ordinary contract tariffs.
Add contents and liability insurance, in the region of €150 to €300 a year for an apartment, internet, and any parking charged separately. Public transport is free nationwide, so that line is zero.
Line six: the reserve, which is the one people delete
Decisions taken by the general assembly bind every owner and the syndic pursues recovery on its own initiative. A special call for funds is not a bill you can defer.
Size the reserve against the building rather than a rule of thumb: the minutes of the last three general assemblies, the reconciled charges, the works fund balance and the level of arrears across the co-ownership. An older building with a thin fund and a facade approaching renewal warrants considerably more than a new build.
A worked figure
A €750,000 apartment bought by a couple, both first-time buyers with full allowances. Duties of €52,500 are absorbed entirely by the combined €80,000 credit, leaving the statutory €100 and €27,500 of credit available for the future. Emoluments with VAT, disbursements and the mortgage deed remain payable in cash.
Change one variable: if only one partner is named on the deed, €40,000 applies against €52,500 and €12,500 becomes payable. Same property, different paperwork.
Total acquisition costs commonly land between roughly 8% and 13% of the price for owner-occupiers after the credit, and materially higher for investors who cannot claim it at all.
Three questions we are asked
How long do I need to hold to break even? Long enough for appreciation to cover roughly 10% of transaction friction in both directions. That is a horizon question rather than a market forecast.
Are charges negotiable? No. They are voted at the assembly and allocated by millièmes recorded in the acte de base. What is negotiable is the price of a lot whose building carries known liabilities.
Should I choose a building with low charges? Choose one with predictable charges, which is not the same thing. Deferred maintenance produces low charges followed by a special call for funds.
The six lines on one sheet
Write them separately rather than as a single number, because they behave differently and only one of them is negotiable.
Acquisition cost, calculated with your actual Bëllegen Akt position rather than a generic 7%. Mortgage service, sized against your real loan-to-value ceiling. Ordinary charges, taken from two years of reconciled accounts rather than the monthly provision. The works fund contribution for this specific lot. Your own running costs, dominated by the energy class. And the reserve, sized against the building's documented liabilities.
When the arithmetic gets tight, the line most commonly deleted is the last one. Keeping it visible makes that deletion a decision rather than an accident.
Three questions we are asked
Does the Bëllegen Akt cover the notary's fee? No. It reduces registration and transcription duties only. Emoluments, disbursements and mortgage costs remain payable even where the credit absorbs the duties entirely.
Can acquisition costs be financed? Generally not, and they should be planned as cash from the outset.
Editorial note: This is a framework for a housing decision, not advice on a specific property. Communal rules, building regulations and transport works in Luxembourg change. Verify with your commune, your lease or règlement de copropriété, Luxtram and guichet.lu before relying on any of the above.