Dutch Tax System and the 30% Ruling

Dutch personal income tax (inkomstenbelasting, IB) is built around a three-box structure. Unlike Korea's comprehensive income tax, the Dutch system separates income by character — box 1 (employment, business, pensions), box 2 (substantial-shareholding dividends and gains), and box 3 (capital, savings, investment) — and applies different rates to each. On top of that sits the 30% ruling, a powerful tax concession for foreign specialists that Korean IT engineers and researchers most often ask about.

Box 1: employment and business income (progressive)

• 2024 two-bracket schedule: roughly 36.97% (including national insurance contributions) up to about €75,500, and 49.5% above that.
• Social insurance contributions (volksverzekeringen) are folded into the box 1 rate, which makes the headline rate look high. The effective burden should be assessed after general and labour tax credits (heffingskorting, arbeidskorting).

Box 2: substantial-shareholding dividends and gains

• Applies to dividends and capital gains from companies in which you hold 5% or more (aanmerkelijk belang).
• 2024 two-step structure: 24.5% up to roughly €67,000, 31% above that.

Box 3: capital, savings, investment

• Savings, equities, rental property and similar assets are taxed under a deemed-yield (forfaitaire) regime; following the 2023 Supreme Court ruling, the system is gradually shifting toward actual-return taxation (details change yearly).
• 2024 personal exemption (heffingvrij vermogen) is around €57,000 per person.

30% Ruling (foreign-specialist tax concession)

This is the headline benefit for IT engineers, researchers, and other highly skilled workers recruited from Korea.

• Eligibility: lived more than 150 km outside the Dutch border for at least 16 of the 24 months before arrival, met the salary threshold (about €46,107 in 2024 for the standard rule, around €35,048 for PhDs under 30), and recruited by an IND-recognised sponsor.
• Benefit: up to 30% of gross salary can be paid tax-free. On a €70,000 salary, around €21,000 becomes tax-free, with box 1 rates applying only to the remainder.
• Duration: previously 5 years, but from 2024 it is gradually scaled down over 5 years (30% for the first 20 months, 20% for the next 20, 10% for the final 20). Earlier applicants may benefit from transitional rules.
• Partial non-resident status: during the 30% ruling period you used to be able to elect non-resident treatment for boxes 2 and 3, sheltering foreign assets. This option is being abolished from 2025 (verify the current state on government.nl).

What Koreans often miss

• The 30% ruling is not automatic. You must apply to the Belastingdienst together with your employer within four months of arrival to get the ruling backdated to your start date.
• The Korea–Netherlands tax treaty provides double-taxation relief, but failing to declare Korean-side assets means box 3 tax can be missed.
• A one-off consultation with a tax adviser (belastingadviseur or seasoned accountant) in your first year is generally recommended.

Official guidance: Belastingdienst: 30% facility, government.nl: Income tax