Federal mortgage interest deduction abolished in 2026: what happens to your old loan?

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📅 Last updated: 30 June 2026
 ·  ⏱ Reading time: 11 min
 ·  🏷 Topic: Federal mortgage interest deduction, Law of 18 December 2025, regional woonbonus, long-term saving
 ·  🇧🇪 For: Belgian homeowners and investors with an outstanding mortgage loan

On this page

  1. What exactly changed in assessment year 2026?
  2. Federal: no transitional regime — old loans hit too
  3. What remains federally: long-term saving for pre-2024 loans
  4. Regional: each region with its own abolition date
  5. Decision tree + table: which regime applies to your loan?
  6. Three scenarios: how does your tax return change concretely?
  7. Practical checklist
  8. Sources & further reading

For anyone who bought a second home in 2010, a Brussels apartment in 2018 or a rental property in Antwerp in 2022: the mortgage interest deduction you were counting on largely disappears in 2026. The federal government bundled in the Law of 18 December 2025 on miscellaneous provisions (Wet van 18 december 2025 houdende diverse bepalingen) (Belgian Official Gazette 30 December 2025, numac 2025009647) the abolition of five federal real-estate benefits at once. The Federal Public Service Finance clarified the consequences in Circular 2026/C/2 of 5 January 2026 on federal real-estate taxation – changes from assessment year 2026 (consulted 2026-05-20).

The core is brutally simple: from assessment year 2026 (= 2025 income) the federal interest deduction for loans that do not finance your own home no longer exists — regardless of when you signed the loan. There is no transitional regime for older credits. The Council of State suggested a distinction between recent and older debts, but the government did not follow that advice and motivated its choice with the “extremely difficult budgetary situation”.

This article lays out the federal changes, describes what remains for old loans, compares the three regions and ends with a table + checklist you can apply immediately to your own file.

What exactly changed in assessment year 2026?

The Law of 18 December 2025 abolishes with a single stroke five federal tax benefits that shaped the Belgian housing and investment landscape for decades. An overview as summarised by the FPS Finance circular 2026/C/2 and the analysis from KBC Private Banking (consulted 2026-05-17):

  1. The federal ordinary interest deduction for debts incurred to acquire or maintain immovable property that is not your own home (article 14 ITC92, amended). No transitional period.
  2. The federal woonbonus (codes 1370/2370) for pre-2014 loans that once financed the own home but no longer do since before 1 January 2016 (article 539 ITC92, expires after assessment year 2025).
  3. The federal building saving (codes 1355/2355), originally intended for loans signed before 2005 (article 526 § 2 ITC92, expires).
  4. The additional interest reduction (codes 1138/2138 and 1139/2139) for loans from 2005 to 2013 for new builds or heavy renovation (article 526 § 1 ITC92, expires).
  5. The tax reduction for green loans signed between 2009 and 2011 (article 14524 ITC92, repealed). The bank bonification of 1.5% on those credits — a subsidy, not a tax reduction — is expected to remain in place for as long as the loan term runs; check with your credit institution whether that bonification still applies to your contract after the tax abolition.

The differences between those five benefits are largely historical. For anyone who simply wants to know whether their deduction still works in 2026: the answer is, for the federal tax return, nearly always no, with one exception covered in detail below.

Federal: no transitional regime — old loans hit too

The most politically striking feature of the reform is the absence of any grandfather clause for the interest deduction itself. Anyone who bought a rented apartment in 2015 with a €200,000 25-year loan still pays interest to the bank — but from assessment year 2026 onwards can no longer deduct that interest from their taxable immovable income. The Council of State’s advice to treat recent and old debts differently was, as Flamée & Partners summarises (consulted 2026-05-17), not followed.

That hits three groups hardest:

  • Owners of a second home (coastal flat, mountain chalet) whose loan is still running.
  • Private landlords with one or more rental properties held privately.
  • Co-owners in family undivided estates where one party financed the loan for the entire property.

For loans that still run for many years — think of a 25-year loan that started in 2020 — several thousand euros per year in tax benefit disappear this way. As an illustrative example: a landlord with €5,000 in annual interest expense and a marginal rate around 50% quickly loses €2,000 to €2,500 per year. Over a remaining term of fifteen years that adds up to €30,000 to €37,500 in extra tax burden.

Indicative — actual loss depends on your full tax picture (effective marginal rate after progressivity, municipal surcharge, other immovable income). For a precise estimate consult your tax assessment notice or a tax adviser.

⚠️ Important nuance. What has been abolished is only the tax reduction or deduction at federal level. Your loan simply continues. The capital repayment remains a private expense and the outstanding-balance insurance premium stays payable for as long as the contract exists. So what changes is not your cash flow to the bank — but what you recover afterwards via your tax return.

What remains federally: long-term saving for pre-2024 loans

Among all those abolitions, one federal benefit remains intact, subject to strict conditions. Long-term saving (article 1451, 2° and 3° ITC92) remains available for capital repayments and outstanding-balance insurance premiums on loans that meet each of the three following conditions:

  • the loan was signed before 1 January 2024;
  • the loan was taken out for the own and only home at the time of signing;
  • the mortgage registration has a duration of at least ten years.

The benefit amounts to a 30% tax reduction on deductible expenses, capped at the first tranche of the long-term saving ceiling. For assessment year 2026 this ceiling is at most €2,450 of expenses per taxpayer. Through the Law of 18 December 2025, this amount is frozen at the AY 2025 level for assessment years 2026 through 2030 — no further indexation during that period (confirmed by Practicali — indexed amounts assessment year 2026, consulted 2026-05-20). The Federal Public Service Finance uses tax-return codes 1358/2358 for this item.

So anyone who quickly signed a loan in 2023 for their own home can, until the end of the loan term, continue to deduct their capital repayments and their outstanding-balance insurance premium — but not the interest on those (the latter disappears from income year 2025 onwards). For loans from 1 January 2024 onwards this channel also disappears: there is then no federal housing benefit of any kind available.

Regional: each region with its own abolition date

The own home has been a regional competence since 2014. Each region chose its own pace to phase out the old woonbonus or Chèque Habitat and replace it with reduced registration duties. The state of play according to Wikifin (FSMA) (consulted 2026-05-17):

  • Flanders. Since 1 January 2020 the integrated woonbonus has been abolished for new loans. Anyone who signed a loan before that date for their sole and own home keeps the benefit — provided the loan is not substantively amended. An internal refinancing with the same bank or an external switch may, depending on how it is structured legally, jeopardise the retention of the woonbonus. The compensation consists of reduced registration duties of 2% for the sole and own home.
  • Wallonia. The Chèque Habitat replaced the old woonbonus in 2016 and was itself abolished on 1 January 2025. Anyone who signed their loan between 1 January 2016 and 31 December 2024 keeps the benefit. From 2025 onwards there is no Walloon tax benefit for a new mortgage loan; the region has since also worked with reduced registration duties (3% for the sole and own home).
  • Brussels-Capital Region. The woonbonus was abolished here as early as 1 January 2017. For loans signed before that date the old regime continues to apply. The compensation was an enhanced registration abatement.

💡 Conclusion for 2026. Since 1 January 2025 there is in no region any remaining tax benefit attached to a new mortgage loan for the own home (as confirmed by Wikifin). Anyone buying now trades a tax benefit on the loan for lower purchase costs via registration duties. Anyone who borrowed earlier depends on the region where the home is located and the date of their loan.

Decision tree + table: which regime applies to your loan?

Decision tree federal and regional housing taxation assessment year 2026 Flow diagram visualising the choice between federal long-term saving, regional woonbonus or no deduction at all, based on loan date and type of home. Is the home your own home?

NO YES

Rental / 2nd home No federal interest deduction left

Loan signed before 2024?

YES NO

Federal long-term saving capital + outstanding-balance insurance · codes 1358/2358

No federal benefit left

In addition: regional? VL pre-2020 woonbonus · WAL 2016–2024 chèque · BXL pre-2017

Step 1 = type of home. Step 2 = loan date. Step 3 = region.
Loan date Own home in VL Own home in WAL Own home in BXL Non-own home (anywhere)
Before 2005 Federal building saving — abolished AY 2026 Same Same Federal interest deduction — abolished AY 2026
2005 – 2013 Additional interest reduction — abolished AY 2026 Same Same Abolished AY 2026
2014 – 31/12/2016 Flemish integrated woonbonus Federal woonbonus (regionalised 2016) Woonbonus until loan of 31/12/2016 Abolished AY 2026
1/1/2017 – 31/12/2019 Flemish integrated woonbonus Chèque Habitat No benefit left Abolished AY 2026
1/1/2020 – 31/12/2023 No Flemish woonbonus — reduced registration 2% Chèque Habitat No benefit Abolished AY 2026
1/1/2024 – 31/12/2024 No woonbonus Chèque Habitat (until 31/12/2024) No benefit Abolished AY 2026
From 1/1/2025 No benefit — registration 2% No Chèque Habitat left — registration 3% No benefit Abolished AY 2026

ℹ️ The table summarises the main categories. For loans falling around an abolition date or for refinancings that may break the old regime, you are best off consulting the Wikifin tool and/or your tax adviser.

ℹ️ Note on the “Non-own home (anywhere)” column: for loans signed before 2005 a federal building saving never existed for a non-own home — only the ordinary interest deduction (art. 14 ITC92). “Abolished AY 2026” in that row therefore refers exclusively to the disappearance of the ordinary interest deduction, not to a building-saving benefit that would also have applied to non-own homes.


ℹ️ Note on registration duties VL 2% / WAL 3%: the reduced rate of 2% (Flanders) and 3% (Wallonia) applies to purchase deeds for a sole and own home concluded from 1 January 2025 onwards. Borrowers who signed their loan before 2025 did not retroactively receive that lower rate on their original purchase; the percentages in the table indicate the current compensation mechanism for new buyers. From 1 January 2026 stricter application conditions apply in Flanders for the 2% rate: the buyer must register at the address of the property within three years and maintain that registration for at least one year; in addition the 2% rate applies only to full ownership (no split with usufruct) and only to natural persons (no company purchases). The cutoff is the provisional sales agreement date (compromis): purchases for which the compromis was signed before 1 January 2026 still fall under the more lenient 2025 conditions, even if the notarial deed is executed in 2026 (Andersen Belgium, consulted 2026-06-30). Consult your notary for your specific situation.

Three scenarios: how does your tax return change concretely?

Scenario 1 — Antwerp couple, 2018 loan on own home in Flanders. The loan falls under the Flemish integrated woonbonus (pre-2020 grandfathered). At federal level almost nothing changes for them in 2026, because they were already covered by the regional regime anyway. The federal interest deduction for own homes had in any event already been transferred to the regions in 2014. Point of attention: check the conditions if refinancing. According to Circular 2025/C/35 on the Flemish woonbonus (consulted 2026-05-20) a refinancing — internal at the same bank or external at another bank — is treated as a continuation of the original loan provided that (a) the refinancing serves to repay the outstanding principal and (b) the combined duration of both contracts together totals at least ten years. Any surplus above the outstanding principal does not fall under the regional benefit. An internal adjustment via an addendum at the same bank is administratively simpler — and the reinvestment fee on an interest-rate adjustment by addendum has been abolished (Law of 3 May 2024, see also Test-Aankoop) — but the legal criterion for retention of the woonbonus is the same for both paths.

Indicative — actual loss depends on your full tax picture (municipal surcharge, other deductions, household composition). Consult your tax assessment notice or a tax adviser for your own file.

The federal Law of 3 May 2024 applies to all Belgian mortgage credits and not only to Flemish loans. Anyone wishing to retain their Chèque Habitat (Wallonia) or their Brussels pre-2017 woonbonus during an interest-rate adjustment can follow the same reasoning: an addendum at the current bank avoids a “real” refinancing and the associated reinvestment fee. The regional benefit itself is only retained if the adjustment qualifies as a continuation of the original loan — check the regional FAQ or ask your tax adviser.

Scenario 2 — Brussels owner, 2022 loan for a rental property. Here the reform hits hard. The interest on that loan was deductible from taxable immovable income up to and including income year 2024. From income year 2025 onwards that deduction disappears entirely. At a marginal rate of 50% and an interest expense of, say, €4,500 per year, the loss is approximately €2,250 per year in federal taxes — over a remaining term of twenty years therefore around €45,000 gross. That is real money which appears for the first time in 2025 on the 2026 tax return.

Indicative — actual loss depends on your full tax picture (effective marginal rate, municipal surcharge, other immovable income and deductions).

Scenario 3 — Antwerp self-employed person, own home bought in 2020 (Flanders). The loan falls between the abolition of the Flemish woonbonus (1 January 2020) and the abolition of the federal long-term saving for new loans (1 January 2024). For federal long-term saving (codes 1358/2358) he qualifies — it is the own and only home, signed before 1 January 2024 and with a mortgage registration of at least ten years. He therefore keeps a 30% reduction on his capital repayments and outstanding-balance insurance premium up to the first tranche of the ceiling (€2,450 in 2025). The interest deduction disappears federally regardless — it was already unavailable for the own home since 2014.

Practical checklist

  • ☐ Identify per loan whether it finances the own home or another property (cadastral number + address in your credit deed usually suffices).
  • ☐ Note the signing date of each mortgage loan and the region where the home is located — that determines your regime.
  • ☐ Review your tax slips (wage slip 281.10, slip 281.61 long-term saving) for codes 1370/2370, 1355/2355, 1138-1139/2138-2139, 1358/2358: compare with assessment year 2025 whether those codes stay empty in assessment year 2026.
  • ☐ Deduct nothing more under the abolished rubrics in your 2026 tax return — Tax-on-Web will make those fields inaccessible per the announcement in Circular 2026/C/2.

  • ☐ Re-plan your yield as a landlord: calculate the new net cash flow without the old interest deduction (feel free to use Wikifin’s IMMOsimulator).

  • ☐ Do not amend your loan impulsively if it still falls under the Flemish woonbonus, Chèque Habitat or Brussels woonbonus — a refinancing can break grandfather rights. Ask your bank in writing what the consequences of an amendment would be.
  • ☐ Check whether you qualify for federal long-term saving if your loan was signed before 1 January 2024 for your own home.

Sources & further reading

Primary sources (statutory):

Educational portal sources (public institutions):

Secondary analysis (law and accounting firms):

For educational purposes only. This article is not investment advice, not a recommendation and not a personalised analysis. The author is not registered with the FSMA. Always consult an authorised adviser before taking financial decisions. Full disclaimer →


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