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€2,352 back. Here's how taxx.lu customers do it.
taxx.lu customers got back an average of €2,352 on their Luxembourg tax return. Find out which deductions make it happen and how to maximise yours.
That's the average refund taxx.lu customers got back on their tax return last year. Not a typo. Not a best-case scenario. The average.
Some got less. Some got a lot more. But the point is the same: thousands of people working in Luxembourg are leaving money on the table. Either because they don't file a tax return at all, or because they file one without fully understanding what they can claim.
Let's fix that. Here's where those refunds come from, what you might be missing, and how taxx.lu makes sure you get every euro you're owed.
Where does the money come from?
Luxembourg's tax system is actually pretty generous when it comes to deductions. The problem? Most people don't know everything they're entitled to. Or they know the basics but miss the details that make a real difference.
Here are the main deductions that feed into refunds like these.
Mortgage interest on your main residence
If you bought your home, you can deduct the interest on your mortgage. Since the 2024 tax year, the deductible ceiling depends on the date of availability of your property (when it was ready to be lived in). It applies per person in the household: you, your spouse or partner, and each dependent child.
| Date of availability | Deductible limit per person per year |
|---|---|
| After 31/12/2023 | Full deduction (no cap) |
| Between 01/01/2020 and 31/12/2023 | €4,000 |
| Between 01/01/2015 and 31/12/2019 | €3,000 |
| Before 01/01/2015 | €2,000 |
Bought recently (post-2023)? You can deduct 100% of your mortgage interest. No cap. For a couple with one child whose property became available between 2020 and 2023, that's up to €12,000 in deductible interest per year. Even for properties available before 2015, a household of three can still deduct up to €6,000 annually.
Private pension plan (art. 111bis)
This is one of the most powerful tools in the Luxembourg tax toolkit. Since January 2026, you can deduct up to €4,500 per taxpayer per year on contributions to a private pension contract. At a marginal tax rate of 35%, that's a saving of €1,575, just from this one deduction. And yes, it applies to each spouse in a jointly taxed couple.
Quick maths
A couple where both partners max out their 111bis contributions? That's €9,000 in deductions. At a 35% marginal rate, you're looking at over €3,000 back from pension savings alone.
Insurance premiums
Car insurance (the civil liability part), home insurance (only the liability portion), supplementary health insurance, life insurance: all deductible under article 111 of the Luxembourg income tax code, with a combined ceiling of €672 per person in the household.
Home savings plans
Saving to buy, renovate, or pay off a home? Contributions to a qualifying home savings plan are deductible. The ceiling is €672 per member of the household, or €1,344 if the youngest taxpayer is under 41.
Childcare and household help
Crèche fees, after-school care, or a registered household employee: deductible up to €5,400 per year. For families with young children, this is often a big one.
Interest on personal loans
Student loans, car loans, consumer credit: the interest you pay is deductible up to €672 per person in the household.
Donations
Gifts to recognised public-interest organisations are deductible, as long as total donations come to at least €120 per year.
Extraordinary charges
Unreimbursed medical expenses, dental work, divorce costs, even prescription diets: all potentially deductible, provided they exceed a threshold (called the "normal charge") linked to your income and family situation. A lot of people skip this section because the calculation looks complicated. It doesn't have to be.
taxx.lu calculates the threshold for you
No need to figure out the normal charge yourself. Based on your income, tax class, and household composition, taxx.lu calculates and displays your threshold directly in the extraordinary charges section. You can see straight away whether your expenses qualify for a deduction.
Keep your documents
Invoices, receipts, proof of non-reimbursement (from the CNS, DKV, CMCM, etc.): hang on to all of them. The tax office can ask for evidence at any time.
So what does €2,352 actually look like?
Let's put a face on it. Three profiles, all based on realistic scenarios.
Sophie: cross-border worker from Metz
Sophie commutes from France to Luxembourg-City every day. She earns €65,000 per year and files as a non-resident opting for tax assimilation. She deducts her car and home insurance premiums, her supplementary health insurance, interest on her car loan, a home savings plan, and a private pension plan she took out last year.
She had no idea she could claim most of these until she filled out her return on taxx.lu and the Opti-Score flagged them.
Her refund: €2,352. Right on the average.
Marc and Julie: young couple in Gasperich
Marc and Julie bought their apartment in 2023. Two salaries, two sets of deductible insurance premiums, mortgage interest on their main residence, childcare costs for their toddler, and a joint home savings plan. They're well above average.
Their refund: €4,600.
André: single resident, long-time renter
André earns €52,000, rents in Bonnevoie, and figured a tax return wouldn't do much for him. But between his private pension contributions, his supplementary health insurance, his car and home insurance premiums, and a few hundred euros in donations, the deductions stacked up.
His refund: €1,340. Not the highest, but absolutely worth the 45 minutes it took him on taxx.lu.
Cross-border workers, this one's for you
If at least 90% of your worldwide income is taxable in Luxembourg (or 50% of professional income for Belgian residents), you can opt for tax assimilation. That means the same deductions as a Luxembourg resident. Many cross-border workers don't know this and miss out on thousands of euros every year.
What makes taxx.lu different?
Filing a tax return in Luxembourg isn't rocket science. But doing it well takes more than just filling in boxes. Here's where taxx.lu earns its keep.
See your refund in real time
As you fill in your return, taxx.lu calculates your estimated refund (or amount owed) in real time. No surprises. No waiting until the ACD sends you a letter six months later. You see the impact of every deduction the moment you enter it.
The Opti-Score: plan ahead for next year's return
Once your return is done, taxx.lu generates your Opti-Score: a rating from 0 to 100 that shows how well you've optimised your deductions. A score of 0 means loads of untapped potential. A score of 100 means you've maxed everything out.
Here's the thing: the Opti-Score is forward-looking. It tells you what you can do this year to improve next year's tax return. Haven't taken out a private pension plan? Not claiming insurance premiums you're already paying? Any action you take now can only be declared on your next return. The Opti-Score gives you the roadmap.
Your Opti-Score is your roadmap for next year
Filing your 2025 return now gives you a clear picture of what's missing. You then have the rest of 2026 to act on those recommendations: take out a private pension plan, adjust your insurance, boost your home savings. Those changes will be deductible on your 2026 return, filed in 2027.
Expert review and tax assessment check (avis d'imposition)
Here's something most people don't think about: even after you file, the tax office can make mistakes. The tax assessment notice (avis d'imposition) you receive from the ACD may contain errors. A deduction that wasn't applied. A calculation that doesn't match your return. A bracket that was applied incorrectly.
With taxx.lu's Plus, Premium, and Platinum packages, the team reviews your tax assessment notice once you receive it and, if needed, drafts a professional appeal letter on your behalf. This safety net can be worth hundreds of euros, and it's something you simply don't get with MyGuichet.
The tax assessment check is a game-changer
The tax office processes thousands of returns and mistakes happen: a forgotten deduction, a wrong bracket, an amount that doesn't add up. If your assessment doesn't match your taxx.lu result, just send it to the team. With the Plus, Premium, and Platinum packages, they'll investigate and prepare an appeal letter if the error is on the administration's side.
AutoScan: less typing, fewer mistakes
Scan your tax certificates or import your PDFs, and taxx.lu's AutoScan extracts the amounts and pre-fills your return. It works with most Luxembourg certificates, though pre-filled data should always be checked. Foreign documents may not be recognised by AutoScan and might need to be entered manually.
Form 100 and Form 163
Whether you need the standard tax return (form 100) or the annual adjustment (form 163), taxx.lu handles both. The system automatically determines which form fits your situation. No guesswork.
How much does it cost?
taxx.lu offers several packages depending on how much support you want:
- Standard (€69): You complete your return yourself with full guidance, auto-calculations, Opti-Score, and real-time estimates.
- Plus (€119): Everything in Standard, plus a manual review by a tax expert, and, a check of your tax assessment notice, and a letter of appeal if needed.
- Premium (€199): Everything in Plus, plus a video call with a tax expert and the option to have your return printed and ready to send.
- Platinum (from €290): The full-service option. taxx.lu's team handles everything for you.
Need to declare rental income, capital gains on real estate, or file a form 166? These are available as add-on annexes: form 190 (rental income), form 700 (capital gains), and form 166 (married cross-border workers) at €59 each.
The ROI speaks for itself
The average refund is €2,352. The Standard package costs €69. That's a return of over 34x. Even the Platinum package pays for itself many times over.
The 2025 tax return is live. Start now.
The official ACD forms are available from April 7, but your 2025 tax return is already ready to fill in on taxx.lu. The earlier you file, the sooner the ACD processes your return, and the sooner your refund hits your account.
Creating an account is free. Running a simulation is free. You only pay when you're ready to download the final form.
€2,352 is the average. Yours could be more.
