Outlook · Bill 36748

Four scenarios for Box 3

What can the Senate do, and how likely is each scenario? Our assessment after the May 19, 2026 expert hearing.

Updated May 19, 2026

Low10%

Pass unchanged

The Senate passes the current text of bill 36748 without a novelle. Entry into force as planned on January 1, 2028.

Triggers

Coalition of SP, Volt and GroenLinks-PvdA wins over undecided senators
The cabinet makes no substantive novelle commitment
Time pressure from Belastingdienst and chain partners outweighs substantive criticism

Timing

Vote in June/July 2026

Impact

Belastingdienst and chain partners hit the one-year-and-nine-months lead time for 2028 — barely. Announced Vastgoed Belang litigation proceeds; legal risk remains.

Medium35%

Pass with novelle

The bill is adopted, followed by a novelle that repairs the main points of criticism: loss offset, real-estate deemed return, life events. Entry into force possibly delayed to 2029.

Triggers

State Secretary Eerenberg files a concrete adjustment letter in summer 2026
Novelle is filed around Prinsjesdag 2026
Senators accept parallel treatment as a compromise

Timing

Adoption autumn 2026, novelle Q1 2027, entry into force January 1, 2028 or 2029

Impact

Two-track model with uncertainty about the final shape into 2027. Banks and insurers build against a moving target.

High45%

Delay to 2029

The Senate does not vote until the novelle is fully on the table. Entry into force shifts to January 1, 2029, possibly with a switch to a capital-gains tax instead of an accrual tax.

Triggers

A majority of senators expresses preference for a capital-gains tax
Belastingdienst and chain partners signal that 2028 is no longer feasible
The coalition target (full capital-gains tax by Prinsjesdag 2029) is brought forward

Timing

Definitive decision Q4 2026 / Q1 2027

Impact

The bridging law (36204) remains the active system through end-2028. Taxpayers continue using tegenbewijs via current forms. The investment climate gets a year of breathing room.

Low10%

Withdraw and redesign

The bill is withdrawn (as Heithuis advised), and the cabinet comes back with a new design that doubles as a tegenbewijs regime. Politically the most radical scenario.

Triggers

Senate forces withdrawal by blocking written rounds
Cabinet voluntarily restarts to limit legal risk
Tweede Kamer majority shifts explicitly toward a capital-gains tax

Timing

Withdrawal Q3 2026, new bill 2027

Impact

Longest path, cleanest end-state. Bridging law dominates through at least 2029. Risk of fresh legal skirmishes around the tegenbewijs regime.

What to watch — upcoming milestones

May 26, 2026Senate second written round
Before summer recess 2026Eerenberg letter on accrual variants and costs
Prinsjesdag September 16, 2026Possible novelle filing
Q4 2026Senate vote or formal delay decision
December 31, 2027Hard deadline: Belastingdienst CoolGen retirement
January 1, 2028Planned entry into force (increasingly uncertain)
Prinsjesdag 2029Final deadline for full capital-gains tax proposal

Back to the May 19 report