Best social insurance fund for self-employed in Belgium (2026)
Updated · figures checked 2 November 2026
The short version
- Your social contributions are the same at every fund: the law sets them. What changes is the management fee each fund adds, the language and the onboarding.
- Lowest verified fee and comfortable in Dutch or French: Xerius.
- Want an English website and an online signup form: Securex, or Group S if you are in Brussels.
- Join before your first day of activity. Late affiliation can bring a fine, and you can only switch fund after several years, on 1 January.
Values link to the provider page we read on the date shown on hover. Prices change: confirm on the provider's site before you sign.
If you start working as a freelancer, consultant or sole trader in Belgium, one of the first obligations is to join a social insurance fund (caisse d’assurances sociales / sociaal verzekeringsfonds). The fund collects your quarterly social contributions and is your link to the social security system for the self-employed, which covers rights such as your pension and health insurance through your mutuality. Many newcomers only discover it when their accountant or the business counter asks which fund they chose.
This guide is for people starting a self-employed activity in Belgium, in main or secondary occupation, who must pick a fund. It compares the eight private approved funds and the public National Aid Fund, using what each fund publishes.
The key point is simple. The contributions themselves are fixed by law and are identical at every fund. Each fund adds a management fee on top, and that fee, the language of service and how easy it is to join are what really differ. For an English speaker who has just arrived, language and online signup can matter as much as a fraction of a percent.
How social contributions work
The rates are the same everywhere
INASTI (the National Institute for the Social Security of the Self-employed, also NISSE / RSVZ) sets the scale. Self-employed in main occupation pay 20.50% on professional income up to €75,024.54 and 14.16% on the part between €75,024.54 and €110,562.42. (source, checked 2 November 2026) The INASTI scale excludes management fees, which vary from one fund to another. (source, checked 2 November 2026)
So when you compare funds, you are comparing the fee added to a legally fixed amount. A difference of one percentage point in fees applies to your contributions, not to your income, which keeps the gap modest in euros but real over years.
Minimums and starters
When you start, you pay provisional contributions based on an estimate, then a regularisation once your actual income is known from your tax assessment. 2026 minimum provisional quarterly contribution (main occupation) is €890.42, calculated on a minimum income of €17,374.08; maximum is €5,103.05 per quarter (before fund management fees). (source, checked 2 November 2026)
People who start for the first time can ask for a lower amount in the first year. Primostarters can ask for a reduced contribution of €459.82 per quarter during their first 4 quarters if estimated income does not exceed €8,972.07, plus a €118.52 reduction in the first quarter. (source, checked 2 November 2026) This helps cash flow at the start, but if your real income turns out higher, the regularisation comes later. Set money aside.
If self-employment is a side activity next to a salaried job, the rules are different. Self-employed in a secondary (complementary) occupation pay nothing below €1,922.16 revalued income; the minimum quarterly contribution above that is €98.51 (2026). (source, checked 2 November 2026)
When to join, and switching
Joining comes before starting. You must join a social insurance fund before starting; otherwise you risk an administrative fine of €500 to €2,000. (source, checked 2 November 2026) If you do nothing, you do not escape: after a formal notice you are affiliated automatically to the public National Aid Fund, as the INASTI FAQ on joining a fund explains.
Changing fund later is possible but limited. You can change fund on 1 January of each year after at least 4 years with your current fund; the new fund handles the formalities. (source, checked 2 November 2026) So the first choice tends to stay with you for years. Choose with the next four years in mind, not only the first quarter.
Which funds are approved
INASTI lists 8 private approved funds (Group S, Xerius, Liantis, Partena Professional, Acerta, Securex-Integrity, Avixi, UCM) plus the public National Aid Fund. (source, checked 2 November 2026) All of them do the same legal job. The comparison below is about cost, language and service.
What a newcomer should check
- Language. Several funds publish their websites in Dutch and French only. Letters about contributions, regularisations and reminders will arrive in that language.
- Online signup. Some funds let you join with an online form; for others we could not confirm an online process.
- Business counter help. Several funds also run or work with an enterprise counter (guichet d’entreprises / ondernemingsloket) that registers you in the Crossroads Bank for Enterprises and activates your VAT number. Doing both in one place saves time.
- The fee figure. Ask for the fund’s current management fee in writing; a few funds do not publish it on their websites.
The social insurance funds compared
1. Xerius 5.9/10
Ranked 1 of 8 rated providers in this guide.
Best for: Cost-focused self-employed who are comfortable in Dutch or French.
Xerius is one of the large private funds, approved by INASTI. Its management fee is 3.05%, which Xerius describes as the lowest in the sector. It is the lowest among the funds whose fee we could verify; the fees of Acerta, Liantis and Group S could not be confirmed. With that fee, the 2026 minimum quarterly contribution for a main occupation comes to €917.58/quarter incl. fee. Xerius publishes a full 2026 tariff table, and states that all its quarterly amounts include the fee.
The drawback for newcomers is language: the English website is No (NL/FR only). The English address we tried returned an error page. Expect your payment notices and correspondence in Dutch or French. Payment notices carry a pay button that pre-fills and schedules the transfer, which reduces the risk of a late payment.
We could not verify an online affiliation flow on the pages fetched: online join is check current offer. Contact is +32 78 15 05 52, info@xerius.be.
Xerius suits self-employed people who want the lowest verified cost and can handle administration in Dutch or French, or who have an accountant who does. If you need English support for every letter, look at Securex or Group S.
- Management fee (% of contributions)
- 3.05%
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- €917.58/quarter incl. fee
- Website in English
- No (NL/FR only)
- Join online
- check current offer
What works
- Lowest published management fee (3.05%)
- Publishes a full 2026 tariff table in NL/FR
Watch out
- No English website found
- Online signup not verified
How this 5.9/10 is calculated
Verified criteria carry 90% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%, 44% after reweighting) | 10/10 | 3.05% management fee, the lowest figure published by any fund verified in this guide [xerius.be]. |
| English accessibility (25%, 28% after reweighting) | 0/10 | Pages found only in Dutch and French (hreflang nl/fr); https://www.xerius.be/en returned HTTP 404. |
| Service (20%, 22% after reweighting) | 5/10 | Phone +32 78 15 05 52 and e-mail published in the INASTI fund list; opening hours not checked. |
| Simplicity (10%) | not verified | Not verifiable on our check date: online affiliation flow not shown on the pages fetched. |
| Digital (5%, 6% after reweighting) | 6/10 | Payment notices carry a 'POM' pay button that pre-fills and schedules the payment [xerius.be FR page]. |
Regulator: INASTI/RSVZ (NISSE), fund code 002 (checked 2026-11-02).
2. Securex 5.6/10
Ranked 2 of 8 rated providers in this guide.
Best for: Newcomers who want an English website and online signup.
Securex runs the approved fund Securex-Integrity. Its management fee is 4.10%, which puts the start-up provisional quarterly contribution for a main occupation at €926.93/quarter incl. fee. That is a little more than at Xerius, for the same legal contributions.
What Securex offers in return is easier access for English speakers. It has an English website: Yes (EN site), with pages on starting as self-employed and on transferring to Securex. Joining is Yes (online form): its French starter page invites you to affiliate through the online form. Clients get the MySecurex portal and an online business counter. Whether support staff and contracts are in English was not confirmed.
Securex advertises switching to it as free of charge, which matters if you are already with another fund and meet the conditions to change.
Contact: +32 78 05 90 10, mybusiness@securex.be.
Securex suits newcomers who want to read about their obligations in English, join online and manage everything from a portal, and who accept a slightly higher fee for that. If cost is your only criterion, Xerius is cheaper.
- Management fee (% of contributions)
- 4.10%
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- €926.93/quarter incl. fee
- Website in English
- Yes (EN site)
- Join online
- Yes (online form)
What works
- English website
- Online affiliation form
- Client portal MySecurex
Watch out
- 4.10% fee
How this 5.6/10 is calculated
Verified criteria carry 100% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | 6/10 | 4.10% management fee, mid-to-high among verified funds [Securex 2026 PDF]. |
| English accessibility (25%) | 4/10 | English website with self-employed and transfer pages; English support/contracts not verified. |
| Service (20%) | 6/10 | Phone and e-mail in the INASTI list; Securex advertises 24/7 accessibility via its MySecurex portal [securex.be/en]. |
| Simplicity (10%) | 7/10 | French page invites starters to affiliate 'via notre formulaire en ligne' [securex.be/fr]. |
| Digital (5%) | 6/10 | MySecurex client portal and online business counter advertised [securex.be/en]. |
Regulator: INASTI/RSVZ (NISSE), fund code 012 (checked 2026-11-02).
3. Partena Professional 5.0/10
Ranked 3 of 8 rated providers in this guide.
Best for: Self-employed already using other Partena services.
Partena Professional runs an approved fund that took over HDP in 2014. Its 2026 tariff PDF was readable and gives a management fee of 4.20%, the highest verified in this guide, and a provisional quarterly contribution for a main occupation at the minimum income level of €927.82/quarter incl. fee.
The rest of the website was behind a bot check, so we could not confirm whether there is an English site (not verified) or an online signup (check current offer). English is therefore left out of its score rather than counted as a weakness, not a confirmed absence or presence of English.
Contact from the INASTI list: +32 2 549 79 40, independant@partena.be.
Partena Professional suits self-employed people who already use other Partena services and value having everything with one group. On fee alone, several funds in this guide are cheaper.
- Management fee (% of contributions)
- 4.20%
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- €927.82/quarter incl. fee
- Website in English
- not verified
- Join online
- check current offer
What works
- Publishes a detailed 2026 tariff PDF
Watch out
- Higher fee (4.20%)
- Website blocked automated check; English not verified
How this 5.0/10 is calculated
Verified criteria carry 60% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%, 67% after reweighting) | 5/10 | 4.20% management fee, among the highest verified in this guide [Partena 2026 tariff PDF]. |
| English accessibility (25%) | not verified | Not verifiable on our check date: partena-professional.be web pages returned a 'Just a moment...' bot check. |
| Service (20%, 33% after reweighting) | 5/10 | Phone +32 2 549 79 40, fax and e-mail published in the INASTI fund list. |
| Simplicity (10%) | not verified | Not verifiable on our check date: onboarding pages behind a bot check. |
| Digital (5%) | not verified | Not verifiable on our check date: digital tools pages behind a bot check. |
Regulator: INASTI/RSVZ (NISSE), fund code 007 (checked 2026-11-02).
4. Avixi 5.0/10
Ranked 4 of 8 rated providers in this guide.
Best for: Dutch-speaking self-employed who want a personal contact person.
Avixi is the fund formed from Incozina, which took over Multipen and L’Entraide; it reports about 37,000 self-employed clients and 17,000 companies. Its management fee is 4%, kept for 2026, and joining is free. Avixi publishes the legal minimum excluding its fee: €890.42 excl. 4% fee (total not published).
The service model is personal: Avixi advertises a fixed client manager and lists offices in Brussels, Mechelen, Bruges and Hasselt, with Ghent and Liège on its about page. Online join is Yes ('start meteen online'), and Avixi says one file covers your fund affiliation, your registration in the Crossroads Bank for Enterprises and your VAT number. The site has a contribution estimator.
The limit is language. The English website is No (NL/FR only), and no English content was found.
Contact: +32 15 45 12 60, info@avixi.be.
Avixi suits Dutch speakers, or people comfortable in Dutch or French, who want one named contact person and a low fee. English-only newcomers will find it harder.
- Management fee (% of contributions)
- 4%
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- €890.42 excl. 4% fee (total not published)
- Website in English
- No (NL/FR only)
- Join online
- Yes ('start meteen online')
What works
- 4% fee, free to join
- Fixed client manager
Watch out
- No English website
How this 5.0/10 is calculated
Verified criteria carry 100% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | 7/10 | 4% management fee, joining free of charge [avixi.be]. |
| English accessibility (25%) | 0/10 | Site declares only NL and FR versions; no English content found. |
| Service (20%) | 6/10 | Fixed client manager advertised; offices listed in Brussel, Mechelen, Brugge, Hasselt (and Gent, Luik on its 'about' page) [avixi.be]. |
| Simplicity (10%) | 7/10 | 'Start meteen online' and one file for affiliation, CBE and VAT number advertised [avixi.be]. |
| Digital (5%) | 5/10 | Online tools and a contribution estimator on the site. |
Regulator: INASTI/RSVZ (NISSE), fund code 013 (checked 2026-11-02).
5. Group S 5.0/10
Ranked 5 of 8 rated providers in this guide.
Best for: English speakers in Brussels who want to join online.
Group S is the fund with INASTI code 001, based in central Brussels. It has an English website (Yes (EN site)) with a page called “Join our Social Insurance Fund”, and an English remuneration simulator. Joining is Yes (online.groups.be), through the Starters & Independents Online application, which also handles other administrative formalities.
The fee could not be checked: the contributions page did not show its content in a plain request, so the fee is check current price and the minimum quarterly amount check current price. Ask Group S for its current fee before you sign. Its English page also reminds starters that joining late can bring an administrative fine.
Contact: +32 2 555 15 20, independant@groups.be.
Group S suits English speakers in Brussels who want to join online and read the explanations in English. If you want to compare fees precisely before choosing, get the figure from Group S in writing first.
- Management fee (% of contributions)
- check current price
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- check current price
- Website in English
- Yes (EN site)
- Join online
- Yes (online.groups.be)
What works
- English website
- Online affiliation
Watch out
- Management fee not published on pages fetched
How this 5.0/10 is calculated
Verified criteria carry 60% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | not verified | Not verifiable on our check date: fee percentage not found on the Group S pages fetched (contributions page content not in static HTML). |
| English accessibility (25%, 42% after reweighting) | 4/10 | English website including a 'Join our Social Insurance Fund' page and an English remuneration simulator; support language not verified. |
| Service (20%, 33% after reweighting) | 5/10 | Phone +32 2 555 15 20 and e-mail published in the INASTI fund list. |
| Simplicity (10%, 17% after reweighting) | 7/10 | 'Join our Social Insurance Fund' button leads to online.groups.be/starters-independents/identification [groups.be/en]. |
| Digital (5%, 8% after reweighting) | 6/10 | 'Starters & Independents Online' app for administrative formalities [groups.be/en]. |
Regulator: INASTI/RSVZ (NISSE), fund code 001 (checked 2026-11-02).
6. Acerta 4.7/10
Ranked 6 of 8 rated providers in this guide.
Best for: Starters who want English information and a combined business-counter start.
Acerta runs an approved social insurance fund (INASTI code 010). Its English starter pages explain the steps of becoming self-employed and say registration in the Crossroads Bank for Enterprises and VAT activation can be arranged online through its start platform, with the VAT activation free when you start through Acerta. English pages: Yes (EN pages).
The fee could not be verified. Acerta’s fee pages blocked our requests with a firewall error, and its English page only says its administrative cost “is the lowest at Acerta”, without a figure. So the fee shows as check current price and the minimum as check current price. Online join for the fund itself is check current offer.
Contact is +32 2 333 27 20, acerta.be/en/myquestion.
Acerta suits starters who want English information and to combine the business counter steps with the fund in one place. Before choosing it, ask for the management fee in writing and compare it with the verified figures in the table.
- Management fee (% of contributions)
- check current price
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- check current price
- Website in English
- Yes (EN pages)
- Join online
- check current offer
What works
- English-language starter pages
- Online start platform (ikwilstarten.be)
Watch out
- Fee % not verifiable today (site blocked automated fetch)
How this 4.7/10 is calculated
Verified criteria carry 60% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | not verified | Not verifiable on our check date: acerta.be fee pages could not be read (web firewall block); its English page only says its administrative cost 'is the lowest at Acerta' [acerta.be/en]. |
| English accessibility (25%, 42% after reweighting) | 4/10 | English web pages exist (e.g. /en/bemyownboss); English support and contracts not verified. |
| Service (20%, 33% after reweighting) | 5/10 | Phone +32 2 333 27 20 and an online question form published in the INASTI fund list. |
| Simplicity (10%, 17% after reweighting) | 6/10 | Its English page says CBE registration and VAT activation can be arranged online via ikwilstarten.be [acerta.be/en]. |
| Digital (5%, 8% after reweighting) | 5/10 | Online start platform ikwilstarten.be mentioned; app features not verified. |
Regulator: INASTI/RSVZ (NISSE), fund code 010 (checked 2026-11-02).
7. National Aid Fund (Caisse nationale auxiliaire / Nationale Hulpkas) 4.6/10
Ranked 7 of 8 rated providers in this guide.
Best for: Self-employed who prefer the public fund (also the default fund for those who never choose).
The National Aid Fund (Caisse nationale auxiliaire / Nationale Hulpkas) is the public social insurance fund run by INASTI itself. It is also the default fund: if you never join a private fund, you end up here after a formal notice.
It has a basic English website (Yes (basic EN site)). The management fee is not published on the pages we checked, as is the minimum quarterly amount, so ask the fund directly. No online tools were visible on its English site, and online join is not published.
Contact: +32 2 546 45 22, mailcnh@rsvz-inasti.fgov.be.
The National Aid Fund suits self-employed people who prefer a public body to a private organisation and do not need extra services such as a business counter or a client portal. Being affiliated here by default after a reminder is not a good way to arrive: you will already have missed the deadline and may face a fine. If you choose it, choose it on purpose.
- Management fee (% of contributions)
- not published
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- not published
- Website in English
- Yes (basic EN site)
- Join online
- not published
What works
- Public fund run by INASTI
- English landing page
Watch out
- Fee not published
- Minimal online services
How this 4.6/10 is calculated
Verified criteria carry 100% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | 5/10 | Public fund of INASTI; management fee not published on the pages fetched. |
| English accessibility (25%) | 4/10 | Basic English website (national-fund.be/en); support language not stated. |
| Service (20%) | 5/10 | Phone lines for self-employed and companies plus e-mail in the INASTI list. |
| Simplicity (10%) | 4/10 | Default fund: you are affiliated automatically if you fail to join a fund within 30 days of a formal notice [INASTI FAQ]. |
| Digital (5%) | 3/10 | No online tools visible on its English site. |
Regulator: INASTI/RSVZ (NISSE), fund code 900 (checked 2026-11-02).
Go to National Aid Fund (Caisse nationale auxiliaire / Nationale Hulpkas)
8. UCM (Caisse d'assurances sociales de l'UCM) 4.5/10
Ranked 8 of 8 rated providers in this guide.
Best for: French-speaking self-employed in Wallonia and Brussels.
The UCM social insurance fund has its head office in Namur. Its management fee is 4.05%, approved by the Minister, and its 2026 minimum quarterly contribution for a main occupation is €926.48/quarter incl. fee. UCM’s 2026 calculation PDF includes clear worked examples at different income levels, which helps you plan.
UCM offers an online start service and individual follow-up by a UCM adviser. Online join: Yes ('Démarrer en ligne').
Its website is in French only: No (FR only). Correspondence and advice will be in French.
Contact: +32 81 32 06 11, cas@ucm.be.
UCM suits French-speaking self-employed people in Wallonia and Brussels who want an adviser and are happy to work in French. It does not suit people who need English or Dutch.
- Management fee (% of contributions)
- 4.05%
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- €926.48/quarter incl. fee
- Website in English
- No (FR only)
- Join online
- Yes ('Démarrer en ligne')
- Contact
- +32 81 32 06 11, cas@ucm.be
What works
- Clear worked examples in its 2026 PDF
- Individual adviser
Watch out
- French only
- 4.05% fee
How this 4.5/10 is calculated
Verified criteria carry 100% of the scoring weight. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | 6/10 | 4.05% management fee approved by the Minister [UCM 2026 calculation PDF]. |
| English accessibility (25%) | 0/10 | Homepage declares only a French hreflang; no English version found. |
| Service (20%) | 6/10 | Phone and e-mail in the INASTI list; UCM offers individual follow-up by a UCM adviser [ucm.be/je-demarre]. |
| Simplicity (10%) | 6/10 | 'Démarrer en ligne' online start service advertised [ucm.be/je-demarre]. |
| Digital (5%) | 5/10 | Online start services mentioned; app not verified. |
Regulator: INASTI/RSVZ (NISSE), fund code 019 (checked 2026-11-02).
Liantis Not enough verified data to rate
Liantis is an approved fund with INASTI code 003 and a Brussels address. We could not check anything else: every page of its website, including its 2026 contributions table, answered “Too Many Requests” when the data was collected. So the fee is check current price, the minimum check current price, the English website not verified and online join check current offer.
The INASTI list publishes its contact details: +32 2 212 22 30, info@liantis.be.
Too few of its points could be verified, English included, so it is not rated (not enough verified data); that reflects missing information rather than a known strength or weakness. If Liantis is on your shortlist, for example because your accountant works with it, ask for its current management fee, whether it offers service in English and how to join online, then compare with the verified figures in the table.
- Management fee (% of contributions)
- check current price
- Min. quarterly contribution 2026 (main occupation, incl. fee)
- check current price
- Website in English
- not verified
- Join online
- check current offer
What works
- Approved fund listed by INASTI
Watch out
- Fee and service details not verified (site blocked automated fetch)
Why this provider is not rated
Verified criteria carry 20% of the scoring weight, below the 60% we need to rate a provider. Criteria we could not verify are left out and the others are reweighted.
| Product quality (40%) | not verified | Not verifiable on our check date: every liantis.be URL returned HTTP 429 Too Many Requests, so the fee could not be read. |
| English accessibility (25%) | not verified | Not verifiable on our check date: every liantis.be URL returned HTTP 429 Too Many Requests. |
| Service (20%, 100% after reweighting) | 5/10 | Phone +32 2 212 22 30 and e-mail published in the INASTI fund list. |
| Simplicity (10%) | not verified | Not verifiable on our check date: onboarding pages blocked (HTTP 429). |
| Digital (5%) | not verified | Not verifiable on our check date: digital tools pages blocked (HTTP 429). |
Regulator: INASTI/RSVZ (NISSE), fund code 003 (checked 2026-11-02).
If you only speak English
Your main options are Securex and Group S, which have English websites and online signup, and Acerta for English starter information. Even at these funds, official letters may arrive in French or Dutch, because the legal languages of Belgium are French, Dutch and German. Ask the fund before you sign whether an English-speaking contact is available and whether its client portal is in English.
If self-employment is a side activity
If you are employed and freelance on the side, you still join a fund before starting, but your contributions depend on your income from the activity, with no contribution at all below a threshold, as INASTI sets out. Self-employed in a secondary (complementary) occupation pay nothing below €1,922.16 revalued income; the minimum quarterly contribution above that is €98.51 (2026). (source, checked 2 November 2026) The management fee still applies to what you pay, so the fund choice matters less in euros, and language and online tools may matter more.
If you are a first-time starter
Ask your fund about the reduced provisional contribution for first-time starters described above, and keep part of every invoice aside for the regularisation that follows your first tax assessments. Several funds (Avixi, Acerta, Group S, Securex) also help with the enterprise counter steps, which can save you a separate visit.
Step by step: joining a social insurance fund
- Decide whether you work as self-employed in main or secondary occupation, and estimate your income for the first year.
- Choose a fund using the table: fee, language, online signup.
- Join before your activity starts, online where the fund allows it, with your identity document and, if you have one, your Belgian national number.
- Register your business in the Crossroads Bank for Enterprises through an enterprise counter, and activate a VAT number if needed. Some funds do this in the same file.
- Ask for the reduced starter contribution if you qualify.
- Pay the quarterly contribution notices on time. Set up a reminder or scheduled payment.
- When your tax assessment arrives, expect a regularisation from the fund for the years concerned.
- If you want to switch later, check the conditions on 1 January and let the new fund handle the formalities.
Our verdict
Contributions are identical at every fund, so the choice comes down to the fee, the language and the onboarding. Xerius comes out ahead in the table. On cost, Xerius stands out, with the lowest verified management fee, for people who can work in Dutch or French. Securex is the best choice for newcomers who want an English website, an online form and a client portal, at a slightly higher fee. Avixi and Group S are alternatives: Avixi for a low fee and a personal contact in Dutch or French, Group S for English speakers in Brussels who join online. Acerta, Liantis and the National Aid Fund could not be fully verified, so ask them for their fee before deciding; Liantis had too few verified points to be rated. UCM is a good fit for French speakers who want an adviser, and Partena Professional has the highest verified fee.
Frequently asked questions
Do social contributions differ between funds?
No. The contribution rates (20.50% / 14.16%) are set by law; only the management fee added by each fund differs. INASTI's scale explicitly excludes these fees. Source.
What is the minimum I pay per quarter in 2026 as a full-time self-employed person?
€890.42 per quarter before the fund's management fee (e.g. €917.58 at Xerius with 3.05%, €927.82 at Partena with 4.20%). Source.
When must I join a fund?
Before your self-employed activity starts. Late affiliation risks a fine of €500 to €2,000, and after a formal notice plus 30 days you are automatically affiliated to the National Aid Fund. Source.
Can I switch funds?
Yes, on 1 January of each year, provided you have been with your current fund for at least 4 years; not if you still owe your current fund. Source.
Is there a lower rate for starters?
Primostarters can request a reduced provisional contribution of €459.82 per quarter for the first 4 quarters if estimated income stays at or below €8,972.07. Source.
What if self-employment is only a side activity?
Below €1,922.16 of revalued income you pay no contributions; above it 20.50% applies with a €98.51 quarterly minimum (2026). Source.
Which funds are officially approved?
Group S, Xerius, Liantis, Partena Professional, Acerta, Securex-Integrity, Avixi and the UCM fund, plus INASTI's public National Aid Fund. Source.
Official sources
- INASTI/NISSE list of social security funds, checked 2 November 2026
- INASTI names and codes of social insurance funds, checked 2 November 2026
- INASTI Cotisations 2026 (PDF, January 2026, reference year 2023, coefficient 1.07236269), checked 2 November 2026
- INASTI FAQ: how much social contributions do I pay, checked 2 November 2026
- INASTI FAQ: joining a social insurance fund, checked 2 November 2026
- INASTI amounts publication page, checked 2 November 2026
- www.inasti.be: Self-employed in main occupation pay 20.50% on professional income up to €75,024.54 and 14.16% on the part between €7… (checked 2 November 2026)
- www.inasti.be: 2026 minimum provisional quarterly contribution (main occupation) is €890.42, calculated on a minimum income of €17,3… (checked 2 November 2026)
- www.inasti.be: Primostarters can ask for a reduced contribution of €459.82 per quarter during their first 4 quarters if estimated in… (checked 2 November 2026)
- www.inasti.be: Self-employed in a secondary (complementary) occupation pay nothing below €1,922.16 revalued income; the minimum quar… (checked 2 November 2026)
- www.inasti.be: The INASTI scale excludes management fees, which vary from one fund to another. (checked 2 November 2026)
- www.inasti.be: You must join a social insurance fund before starting; otherwise you risk an administrative fine of €500 to €2,000. (checked 2 November 2026)
- www.inasti.be: You can change fund on 1 January of each year after at least 4 years with your current fund; the new fund handles the… (checked 2 November 2026)
- www.inasti.be: INASTI lists 8 private approved funds (Group S, Xerius, Liantis, Partena Professional, Acerta, Securex-Integrity, Avi… (checked 2 November 2026)