Belgium taxes a stock option once, at grant, on 18% of the underlying share value plus 1% a year beyond five years, halved to 9% and 0.5% when five conditions are met, if the beneficiary accepts in writing within 60 days. The gain up to exercise is free of income tax and, for employees, of social security. Since 1 January 2026 growth after exercise is taxed at 10% above an annual exemption of EUR 10,000, with a separate scale for stakes of 20% or more. From income year 2026 employers owe 7.5% on lump-sum benefits, options included, above 20% of total pay.
Belgium taxes the option, not the gain
Most countries tax an employee stock option when it pays off: at exercise, or when the shares can be sold. Belgium does the opposite. Under the Law of 26 March 1999 the option is taxed when it is granted, on a fixed percentage of the value of the underlying shares at the offer. After that, the gain up to exercise is free of income tax and social security, however large it turns out to be.
That makes the Belgian regime a bet. If the shares rise, the executive has paid income tax on a slice of the starting value and keeps the rest of the gain. If the shares fall, the tax paid at grant is lost and is never refunded. For an executive who expects growth, it is one of the cheapest ways in Europe to receive equity.
2026 changes the second half of the story. Since 1 January 2026 gains on financial assets are taxed at 10% above an annual exemption, so growth after exercise is no longer free. From the same income year, employers whose lump-sum benefits in kind exceed 20% of pay owe a 7.5% levy on the excess, and 1999-law options count as lump-sum benefits. For the comparison with the Netherlands and Luxembourg, see EU-ESO and Benelux options.
18% or 9%
Of the share value, plus 1% or 0.5% a year beyond five.
60 days
Written acceptance, or the regime does not apply.
10%
Capital gains tax above EUR 10,000 a year, from 2026.
7.5%
On lump-sum benefits above 20% of pay.
The lump sum, the halving conditions and the 60-day rule
Who and what. The 1999 regime covers options granted in connection with professional activity to employees and to company directors. The shares may be those of the employer, a group company or an unrelated company, and the grantor may be foreign.
The 60-day rule. The option is deemed granted on the 60th day after the offer, provided the beneficiary accepts it in writing within that period. Vesting or performance conditions do not postpone the grant.
Valuation. If the options themselves are listed, the benefit is their closing price on the day before the offer. For unlisted options, which is the usual case for executives, the benefit is a lump sum: 18% of the value of the underlying shares at the offer, plus 1% for each year or part of a year by which the term exceeds five years. For listed shares the share value is the market price before the offer; for unlisted shares it is a value the company sets and supports with an auditor's or expert's report.
Halving. The percentages are halved, to 9% and 0.5%, when all of five conditions are met: the exercise price is fixed at the offer; the option cannot be exercised before the end of the third calendar year after the year of the offer, nor after the end of the tenth year after the offer; it cannot be transferred during lifetime; neither the grantor nor a related company covers the risk of a fall in value; and the shares are those of the company where the beneficiary works or of a company that holds a direct or indirect stake in it.
In the money. If the exercise price is below the share value at the offer, the discount is added to the lump sum, and it bears social security. A certain advantage, such as a put option or a promise to make good a loss, is taxed on its own value.
| Term | Standard lump sum | Halved lump sum |
|---|---|---|
| Up to 5 years | 18% | 9% |
| 7 years | 20% | 10% |
| 10 years | 23% | 11.5% |
| More than 10 years | 18% + 1% per year beyond five | Not available |
The benefit is professional income taxed at 25% to 50% plus the municipal surcharge in the year of grant, with payroll withholding: the executive pays cash from salary, not from the shares.
An executive of a Belgian SA is offered 10,000 options on 1 March 2026, exercise price EUR 20, equal to the share value certified at the offer, ten-year term. She accepts in writing on 20 April. The underlying value is EUR 200,000. Without halving the lump sum is 18% plus 5% for the five years beyond five, 23%, so EUR 46,000. At 50% the tax is EUR 23,000, before the municipal surcharge. If the plan meets the five conditions the lump sum is 11.5%, EUR 23,000, and the tax EUR 11,500. Both amounts are due through payroll in 2026. In 2030 she exercises at a share value of EUR 35, paying EUR 200,000 for shares worth EUR 350,000. The EUR 150,000 spread is not taxed.
Missing the 60 days. A late acceptance takes the option outside the 1999 regime. The Minister of Finance's position, as reported by practitioners, is that the option is then taxed at exercise as a purchase of shares at a discount. In example (a) that is EUR 150,000 of employment income at exercise, about EUR 75,000 of tax at 50%, and the social security exemption goes with it. One late signature can multiply the tax several times over.
Law and practice: Law of 26 March 1999 on the Belgian employment action plan, Articles 41 to 47 (Article 42: grant on the 60th day after written acceptance; Article 43: valuation, halving, in-the-money discount; Article 43 §8: certain advantage); Income Tax Code 1992 (CIR 92), Article 31. Loyens & Loeff, 'Tax regime for stock options in Belgium'.
Selling option shares under the 2026 capital gains tax
Until 2025 a private investor could usually sell shares free of tax. The Law of 6 April 2026 introducing a tax on capital gains on financial assets, adopted on 3 April and published on 21 April 2026, ends that for gains realised from 1 January 2026.
Rates. Gains on shares, funds and other financial assets are taxed at 10%. Each taxpayer has an annual exemption of EUR 10,000, indexed; unused exemption can be carried forward in limited steps, check the current figure for your year. Belgian banks withhold 10% at source from 1 June 2026 unless the holder opts out and reports the gain in the return.
Acquisition value. For shares acquired by exercising a 1999-law option, the acquisition value is the share value at exercise, not the exercise price and not the value at grant. The gain up to exercise therefore stays outside both income tax and capital gains tax; only growth after exercise is taxed. Gains accrued before 1 January 2026 are protected by a step-up: the reference value is the value on 31 December 2025. For unlisted shares that value can be fixed by a valuation, which Deloitte notes is possible until 31 December 2027.
Stakes of 20% or more. A founder or executive who holds at least 20% of the company falls under a separate regime: gains up to EUR 1 million are exempt, measured over five years, and the excess is taxed at 1.25% up to EUR 2.5 million, 2.5% up to EUR 5 million, 5% up to EUR 10 million and 10% above. A sale of a substantial stake to a buyer outside the EEA stays at 16.5%.
The executive in example (a) sells the 10,000 shares in 2032 at EUR 50, with her annual exemption unused. The acquisition value is EUR 35, so the taxable gain is EUR 150,000. After the EUR 10,000 exemption, 10% of EUR 140,000 is EUR 14,000. Over the whole life of the grant she has made EUR 300,000 (EUR 50 minus EUR 20, on 10,000 shares). Her tax is EUR 37,000 without halving (EUR 23,000 + EUR 14,000), an effective 12.3%, or EUR 25,500 with halving, 8.5%. The same EUR 300,000 paid as a cash bonus would cost about EUR 150,000 of income tax at 50%, before the municipal surcharge and 13.07% employee social security. With a stake of 20% or more the EUR 150,000 gain would fall inside the EUR 1 million exemption and the sale would be tax-free.
Where it goes wrong. If the share value falls after exercise, the loss can be offset only against gains of the same year; it does not reach back to the tax paid at grant. On emigration, an exit rule taxes latent gains, deferred for moves within the EEA or to states with recovery assistance, and lapsing if no disposal follows within 24 months.
Law and practice: Law of 6 April 2026 introducing a tax on capital gains on financial assets (Belgian Official Gazette, 21 April 2026). Claeys & Engels, 'Analysis of the new capital gains tax' (May 2026); Deloitte Belgium, 'New capital gains tax: impact on share-based remuneration'; KPMG, 'Belgium: new capital gains tax approved'.
Foreign parents, cash-settled awards and option plans sold by banks
Options on shares of a foreign parent. Most Belgian executives in international groups receive options on the parent's shares, often under a US or UK plan. The 1999 law applies, and the parent link satisfies the fifth halving condition. The Belgian employer reports the benefit on the 281.10 form and withholds only if it intervened in the grant. Three points need a Belgian sub-plan or supplement: a written acceptance within 60 days instead of deemed acceptance, an exercise price fixed at the offer, and a bar on exercise before the end of the third calendar year after the offer. Groups often let Belgian participants give a written undertaking not to exercise earlier, so that the halved rate is available without changing the global plan.
Cash-settled awards. A right that pays the increase in share value in cash, such as a stock appreciation right or phantom share, is not an option to acquire shares. It falls outside the 1999 law and is taxed as ordinary pay when it is paid, with social security. Our note on phantom shares and growth shares compares those instruments.
Option plans marketed by banks. Several Belgian banks and specialist providers sell ready-made plans that let an employer pay a bonus in options instead of cash. The employer buys options from the provider, on investment funds or baskets rather than on its own shares, and grants them under the 1999 law. Where the options are tradable, the benefit is their market value at the offer; otherwise the lump sum applies, without halving, because the underlying is not the employer's shares. After a one-year block the options are typically sold back to the provider. With a modest lump sum and no social security, the net result beats a cash bonus.
Three things now press on these plans. First, the 20% rule: a bonus paid largely in lump-sum options is exactly what the 7.5% levy targets, and for directors it can cost the company its reduced rate. Second, the capital gains tax: for these plans the acquisition value is the market value when the options become exercisable, and any further growth before the sale is taxed at 10%. Third, the deductibility of the employer's cost. Practitioner commentary reports a recent court decision upholding the tax authority's refusal to deduct the cost of a plan bought by a management company for its manager, because the performance targets belonged to the client company, not to the management company. Ruling practice leaves deductibility to case-by-case review.
Law and practice: Law of 26 March 1999, Articles 41 to 43; Income Tax Code 1992, Article 49 (deductible expenses). Loyens & Loeff, 'Tax regime for stock options in Belgium' (foreign grantor reporting and withholding); Deloitte Belgium, impact of the capital gains tax on share-based remuneration (bank warrants and OTC options); Forum for the Future, articles on option plan deductibility and on call plans and the capital gains tax.
Management companies, expats and departing executives
Management companies. The 1999 regime is designed for individuals, so groups often grant options to the person behind a management company. The tax administration's circular 2017/C/21 of 13 April 2017 accepts such direct grants but denies the halved rate: an individual who sits on a board only as permanent representative of a management company is valued at 18%, plus 1% a year beyond five. If the management company itself receives the options, the 1999 law does not apply. The option is taxed in the company at its actual value under corporate tax, and later gains on the shares follow the corporate rules, not the 10% personal tax. The company's cost of buying or funding a plan must pass the Article 49 test, documented against targets of the company that pays.
The expat regime. The Law of 18 December 2025 changed the special regime for incoming taxpayers with retroactive effect from 1 January 2025: the tax-free allowance rose from 30% to 35% of pay, the EUR 90,000 cap was removed, and the minimum gross pay fell from EUR 75,000 to EUR 70,000. The regime covers employees and directors in day-to-day management, but not founders or holders of 30% or more of the capital. It does not exempt option benefits: the lump sum is taxed in full in the year of grant. Our page on the expat regime and director pay has the conditions.
Departing executives. Belgium has taxed the option at grant, so a departure does not trigger more income tax on it and does not refund what was paid. The new country may tax the same option at exercise or vesting, and relief is not automatic. Under the OECD Commentary on Article 15, option income is attributed to the employment it rewards, usually grant to vesting. Directors add a second layer: Article 16 lets the state of the company's residence tax board remuneration, and several Belgian treaties extend that article to day-to-day management functions, so check the treaty wording. Our note on moving with stock options in the Benelux works through the cross-border cases.
- Fix the offer date. Offer letter dated, share value and exercise price stated, acceptance form with a 60-day deadline.
- Test halving before the offer. Exercise window, transferability, no loss cover, employer or parent shares.
- Count the 20% early. Run the employer's lump-sum benefits against total pay before a large grant.
- Record the exercise value. It is the acquisition value for the capital gains tax.
Law and practice: Circular 2017/C/21 of 13 April 2017 (options and management companies); Income Tax Code 1992, Articles 32/1 and 32/2 as amended by the Law of 18 December 2025 (Belgian Official Gazette, 30 December 2025), circular 2022/C/47; OECD Model Tax Convention, Commentary on Article 15, paragraphs 12 to 12.15, and Article 16.
Calculate the tax on your grant
Enter the grant and the values you expect at exercise and sale. The calculator applies the 1999 lump sum, the 10% capital gains tax or the scale for stakes of 20% or more, and flags the 7.5% levy and the points that need a closer look.
Belgian option tax: grant vs exit
Enter one grant under the Law of 26 March 1999 and the share values you expect. You get the tax at grant, the capital gains tax at sale, the total and the effective rate on the whole gain, compared with paying the same gain as a cash bonus.
18% or 9% of share value, plus 1% or 0.5% a year beyond five.
Written acceptance or the option is taxed at exercise.
Growth after exercise above EUR 10,000 a year.
Employer, on lump-sum benefits above 20% of pay.
Belgian stock options: frequent questions
When is a Belgian stock option taxed?
At grant, which the Law of 26 March 1999 fixes at the 60th day after the offer, provided the beneficiary accepts in writing within those 60 days. Tax is due on a lump sum in the grant year; exercise is not taxed.
What happens if I accept after the 60 days?
The option falls outside the 1999 regime. It is then taxed at exercise on the full spread between share value and exercise price, and the social security exemption is lost.
Does the new capital gains tax apply to shares from stock options?
Yes, for gains realised from 1 January 2026. The Law of 6 April 2026 taxes gains on financial assets at 10% above an annual exemption of EUR 10,000 (indexed). For shares acquired by exercising a 1999-law option, the acquisition value is the share value at exercise, so only growth after exercise is taxed.
Does the 7.5% contribution hit every stock option grant?
No. It applies only to the part of an employer's lump-sum benefits in kind, such as company cars and 1999-law options, that exceeds 20% of total employee pay on the 281.10 forms, from income year 2026. Benefits taxed at actual value, such as listed warrants, are outside it. For directors there is no levy; a small company may instead lose its reduced corporate tax rate.
Can my management company receive the options instead of me?
It can, but the 1999 regime is built for individuals. A company receiving options is taxed under corporate tax rules, and options granted to you personally as permanent representative of your management company are valued at 18%, not 9%, under circular 2017/C/21. Test the structure before the offer.
I am leaving Belgium. Do my options follow me?
The Belgian tax at grant is already paid and is not refunded. Your new country may tax the same options at exercise, and treaty relief is not automatic because the taxable events differ.
The 1999 exemption and the new 7.5% levy
Employees. The Royal Decree of 5 October 1999 amended Article 19 §2 of the Royal Decree of 28 November 1969 so that a 1999-law option is not wages for social security purposes. Neither the employee's 13.07% nor the employer's contributions are due on the lump sum. Two parts are caught: the in-the-money discount and any certain advantage. The exemption is also lost where options replace pay or a benefit the employee was already entitled to, replace salary or holiday pay, go to an employee who has resigned, or are out of proportion to usual pay. A year-end bonus can be converted only if the agreement under which it is due allows it.
Self-employed directors. A director who is not an employee pays self-employed social contributions on the taxable lump sum, unless other professional income already reaches the annual ceiling for those contributions.
The 20% rule and the 7.5% levy. The Law of 15 July 2026 reforming personal income tax, published in the Belgian Official Gazette on 29 July 2026, caps lump-sum benefits in kind at 20% of total pay from income year 2026 (tax year 2027). The bill was filed on 17 December 2025; references to a 'Law of 17 December 2025' on this point are to the bill. The test runs per employer and per category, on the totals of the 281.10 forms for employees and the 281.20 forms for directors. In scope: company cars, IT and phone equipment, and 1999-law options taxed on a lump sum. Benefits taxed at actual value, such as listed warrants and free shares, are outside.
The test is collective. One executive with a large grant does not trigger the levy if total lump-sum benefits across the workforce stay under 20% of total pay. Where it applies, the levy is 7.5% of the excess only, not of the whole benefit. In example (a), if the whole EUR 46,000 lump sum fell above the ceiling, the employer would owe EUR 3,450.
Law and practice: Royal Decree of 5 October 1999 amending Article 19 §2 of the Royal Decree of 28 November 1969; Law of 12 April 1965, Article 2. Law of 15 July 2026 reforming personal income tax (Belgian Official Gazette, 29 July 2026), bill DOC 56K1243 filed 17 December 2025. Loyens & Loeff and Claeys & Engels analyses of the 20% rule; Securex, 'Warrants en aandelenopties vrij van sociale zekerheidsbijdragen'.