The short answer
B2B market research answers four questions before you commit budget: how many companies fit your segment, what they spend on the problem, how they buy, and who already serves them. In Belgium and the Netherlands you can answer the first two largely with free public data. Statbel counts VAT-registered enterprises by NACE-BEL code, region and employee class, and its structural business statistics give turnover and purchases per sector. CBS StatLine does the same for Dutch businesses by SBI code, size and region, and publishes cost lines per sector. The KBO and KVK open datasets let you count at company level. The last two questions need people: 9 to 17 interviews per homogeneous segment is where published research finds saturation. Then set go/no-go thresholds before you look at the results.
Sources below are the statistics offices', registers' and federations' own pages, read on 1 October 2026.
What the research has to decide
Market research is a decision, not a report: is this segment worth a sales and marketing budget? Keep it to size (counted, not guessed), spend (euros per year on the problem), pain and buying (who decides, what would make them switch) and competition (including doing nothing). The answers feed your value proposition and, if the answer is go, your go-to-market plan.
Step 1: desk research with public sources
Start with what is free.
Source | Country | What you get | Cost | Watch out |
|---|---|---|---|---|
Belgium | Counts by NACE-BEL code, region down to municipality, employee class and legal form; at 31 December 2024 | Free | Location is the registered office | |
Belgium | Turnover, purchases and personnel costs by sector and size class; 2024 data | Free | Excludes agriculture and finance | |
Belgium | Sector aggregates and ratios from filed annual accounts | Free | NACE-BEL 2008, financial years 2009 to 2018 only | |
Belgium | CSV file of all active entities and establishments, with activities and addresses | Free after registration | No direct marketing with personal data | |
Netherlands | Number of businesses by SBI sector, size and legal form, per quarter | Free | Still on SBI 2008 | |
Netherlands | Establishments by SBI sector and region, per year | Free | Counts sites, not companies | |
Netherlands | One row per registration: start date, status, SBI activities, two-digit postcode | Free | BV and NV only; no names, KVK numbers or headcount | |
Both | Sector reports and events; VNO-NCW has more than 140 member branch organisations | Mostly free | Check the method |
Step 2: count companies by activity code and region
Pick the activity codes that describe your buyers: NACE-BEL in Belgium, SBI in the Netherlands. The first four digits of both follow the European NACE list, so counts for the same class line up across the border. Two traps. Belgium moved to NACE-BEL 2025 on 1 January 2025, and KVK moved the Dutch register to SBI 2025 in September 2025, while many CBS tables, including 81589NED, still use SBI 2008. And codes are declared by the companies themselves. Our guides to NACEBEL codes and SBI codes explain where each goes wrong.
Then cut by region and size. Statbel splits VAT-registered enterprises by the region, province and municipality of the registered office and by employee class. CBS table 81578NED counts establishments, not companies: five sites count five times. Size shrinks the headline most, because most Belgian enterprises have no employees: the TAM, SAM and SOM guide works through that ladder, and the Belgian business landscape page has the regional split. Before trusting a count, open 30 to 50 of its companies by hand.
Statistical tables give totals, not the companies behind them. That is where Bizzy helps: you can filter Belgian companies on NACE-BEL codes or Bizzy's own industry taxonomy, combine that with region and company size, and see the count before you export a single name. Belgian records come from the KBO register, the National Bank of Belgium and the Official Gazette; Dutch companies are covered through Creditsafe data. Treat that count as a working figure and re-check it against Statbel or CBS, because codes, size bands and populations differ by source.
Step 3: estimate what the segment spends
The formula: companies in the segment, times the share that buy the category, times annual spend per buyer. Only the first term is counted; label the other two as assumptions until interviews support them.
Belgium. Statbel's structural business statistics give turnover, purchases of goods and services and personnel costs by NACE sector and employee size class. The 2024 edition, published on 23 September 2026, covers 779,949 businesses in industry, construction, trade and services; agriculture and finance are out.
Netherlands. CBS table 81156ned breaks business costs down by sector (SBI 2008) for 2009 to 2024, with separate lines such as outsourced work, communication, other services and purchases of other goods and services.
Filed accounts. NBB.Stat gives free sector aggregates of Belgian annual accounts, but only on NACE-BEL 2008 and for financial years 2009 to 2018. Good for cost structure, not current size.
Sector totals are dominated by the largest firms, so divide by the matching size class. An illustrative calculation: 2,000 companies in your segment, 40% of which buy the category, at 6,000 euros a year each, is a market of 4.8 million euros a year. If interviews later show 15% instead of 40%, the market is 1.8 million.
Step 4: qualitative interviews
How many: a systematic review of empirical saturation studies by Hennink and Kaiser (Social Science & Medicine, 2022) found saturation within 9 to 17 interviews, or 4 to 8 focus groups, in relatively homogeneous groups with narrow objectives; multi-country studies needed more. Plan about twelve per segment, and treat Belgium and the Netherlands, or small and mid-sized companies, as separate segments if they may buy differently.
Whom: mostly non-customers. Talk to budget owners, daily users, recent buyers of an alternative and people who looked and bought nothing.
What to ask: past behaviour, not opinions about your idea.
How do you handle this today, and when did you last deal with it?
What does the current way cost you, in money, hours or missed revenue?
Who was involved the last time you bought something for this, and who signed?
Which alternatives did you look at, and why did you pick the one you use?
What would have to be true for you to switch?
Which budget does this come from, and when is it set?
Log every interview in the same grid, so you can count how many described the problem unprompted, already spend on it, and which alternatives they named.
Step 5: competitor research
List every alternative interviewees named, including spreadsheets and doing nothing. Read each one's website, pricing page and job ads; where they hire salespeople says more than their homepage. For Belgian competitors, filed annual accounts show headcount and its trend (how to look up Belgian annual accounts); small companies may leave turnover out. Note per competitor which segment they serve best and where interviewees were least happy.
Step 6: turn it into a go/no-go
Write thresholds down before you see results, or every number looks good enough. The thresholds below are illustrative.
Criterion | Evidence | Example threshold |
|---|---|---|
Size | Segment count, re-checked | At least 1,500 companies |
Spend | Step 3 estimate | At least 3 million euros a year |
Pain | Interview grid | 7 of 12 describe the problem unprompted |
Buying | Interview grid | A clear budget owner in most interviews |
Competition | Competitor map | A need or segment nobody serves well |
Reachability | Contacts for the companies counted | Contacts for most of the list |
All met is a go. One or two missing usually means narrowing the segment, to one region or size band, and a second, smaller round. Failing on pain and reachability is a no-go, however large the count.
When an agency is still worth paying
An agency earns its fee for a statistically representative survey, price testing across hundreds of buyers, blind interviews with a competitor's customers, or a sector where decision makers will not take your call. Brief them with your own counts and notes, so you pay for the gap, not for desk research.
Frequently asked questions
How do you do B2B market research? Count the companies in your segment with public statistics, estimate their spend, interview about twelve buyers per segment, map the competitors they name, and compare the results with thresholds set in advance.
Where can I find free market data for Belgium and the Netherlands? Statbel and KBO Open Data for Belgium, CBS StatLine and the KVK open dataset for the Netherlands, plus sector federations for context.
How many interviews do you need for market research? Published research finds saturation within 9 to 17 interviews in a fairly homogeneous group. Plan about twelve per segment.
What is the difference between desk research and field research? Desk research uses existing data such as statistics, registers and competitor websites; field research collects new data through interviews and surveys. Do desk research first.
Photo: the view over Liège from the Montagne de Bueren, Michielverbeek, CC BY-SA 4.0, via Wikimedia Commons