TL;DR: Netherlands data enrichment is the easiest in Europe for mobiles. In our first benchmark (15,000 enrichments run in 2025 and 2026, published May 2026), every provider we saw returned 94 to 100% clean mobile formats on Dutch lists. In October 2026 we dialled them. 65% of Kaspr's Dutch numbers were usable, and 35% of the usable ones we dialled reached the right person. That is one of the best rates in Europe. It still means two dials in three go nowhere. Keep your providers, add one for senior roles, and check every number before your team dials.
Every provider works in the Netherlands.
We said that in May 2026, and it still holds for finding numbers. Dutch lists come back clean. Mobiles in the right format, in the right country, from almost any tool.
Then your reps pick up the phone. And a clean number turns out to be a voicemail, a number that rings out, or the wrong person.
Answrd is part of Profitbl, which runs cold calling campaigns across Europe. We ran the enrichments in this post and we dialled the numbers. Here is what we found when we did both.
Is the Netherlands easy for B2B phone enrichment?
Yes. The Netherlands was the cleanest market in our first benchmark for finding mobiles. That benchmark covers 15,000 enrichments, run in 2025 and 2026, for 28 companies across 12 countries. More than 600 were on Dutch lists.
What the earlier runs showed:
- 94 to 100% clean mobile formats across every provider we measured on Dutch lists.
- Five providers at 100% on one Dutch enterprise list. Wiza, Datagma, Forager, ContactOut and Clay's own data each returned only clean mobiles. No landlines across 79 phones.
- One provider took 96% of the wins on a large Dutch retail list, at 94.5% clean mobile format. The providers behind it had little left to find.
- Near zero foreign numbers on Dutch-only lists.
Compare that with your neighbours in our 2025 to 2026 data. In Belgium, partner-level legal lists came back at 67% clean mobile. In Germany, broad cuts dropped to 65%. You can read those stories in our posts on Belgium and DACH.
One honest caveat. Those first benchmark numbers measure the format of the numbers found. They come from waterfalls, where the first provider sees every contact and later ones only see the leftovers. So win share tells you about position more than quality. The full method sits in our European B2B data enrichment report.
What happens when you dial Dutch numbers?
About a third reach the right person. That is our October 2026 answer, from numbers dialled on live campaigns. In May we promised to measure this. Now we have.
Here is Kaspr in the Netherlands, October 2026:
- Usable: 155 of 239 numbers (65%). Usable means a mobile, in the contact's own country, and not a number we already knew was bad.
- Reached the person: 37 of 106 dialled (35%).
And Eficia in the Netherlands, October 2026:
- Usable: 20 of 21 numbers.
- Reached the person: 3 of 13 dialled. That sample is too small to rank.
Across all countries, about 1 in 4 dialled usable mobiles reaches the right person. That holds for the two biggest phone sources we use. Kaspr reached 28% of 1,071 dialled. Eficia reached 26% of 233 dialled.
So the Netherlands beats the European average. Here is how it stacks up against every market where we dialled 40 or more Kaspr numbers (October 2026):
- Sweden and Denmark: 42 to 43% reached the person (101 dialled).
- Netherlands: 35% (106 dialled).
- Germany: 25% (87 dialled).
- France: 22% (46 dialled).
- UK: 21% (333 dialled).
- Switzerland: 20% (40 dialled).
Only the Nordics did better. You can see why in our Nordics post.
Why does a clean Dutch number still miss?
A clean format tells you the number is a mobile in the right country. It tells you nothing about who answers.
Of the 106 usable Kaspr numbers we dialled in the Netherlands, 69 did not reach the person. They rang out. They went to voicemail. Or someone else answered.
So "every provider works" was true for the question our first benchmark asked. A rep cares about one thing. Who picks up?
Every country has this gap. We wrote about it in why Lusha and Kaspr mobiles reach the wrong person. A plain line check does not close it either, as we show in the limits of HLR lookups.
Which providers find Dutch mobiles for senior roles?
Kaspr finds about half on senior roles, and the rest takes a waterfall. Our first benchmark lists were mostly retail and enterprise staff. Our October 2026 data adds a harder list: senior IT and security people.
Here is how our waterfall did on 461 senior IT and security contacts in the Netherlands, Belgium and Luxembourg, at companies with 50 to 249 staff (October 2026). We ran Tomba, FullEnrich and the other newer providers through looot, our data gateway. Kaspr and Eficia ran on their own.
- Kaspr: 225 usable (49%).
- Tomba: 31 usable of 236 tried, for USD 1.78 in total.
- Eficia: 133 usable of 205 tried (65%). 33 of its misses were wrong-country numbers.
- FullEnrich: 1 of 48, because of a credit problem in our setup. That result says nothing about FullEnrich's data.
- Lusha: 0 of 5.
- AI Ark: 0 of 66.
- Prospeo: 2 of 66, for USD 21.45.
Final result: 392 of 461 (85%) with a usable mobile.
Each provider after Kaspr only saw the contacts the ones above it had missed. So read their rates as "what was left after the big two."
Two more October 2026 results matter for Dutch senior lists:
- FullEnrich on senior security people: 14 of 15 usable on a Dutch and Belgian list, and 38 of 52 on a Dutch, Belgian and Luxembourg list. That is the strongest specialist result we saw in Benelux.
- Lusha on a Benelux senior list: 27 billed hits from 58 lookups, and 1 usable own-country mobile. That is about USD 20 per usable number. Most hits were foreign mobiles and direct lines.
FullEnrich has a weak spot too. After Eficia, on mid-level staff at global companies, it found 15 of 97 (October 2026). Many misses there were US or foreign numbers, or numbers other providers had already given us.
Why do cross-border numbers break Benelux lists?
Watch the border. On the Benelux list above, 20 of the misses had only a mobile from a neighbouring country. Most of those were Luxembourg staff on Belgian or French numbers.
That is usually a private phone. We counted those numbers as misses and left them out. A waterfall tool would have counted them as hits.
Belgium and Luxembourg are much harder than the Netherlands. Kaspr's Belgian numbers were 40% usable (16 of 40, October 2026). In Luxembourg, 0 of 13 were usable, all foreign or office lines. If your list mixes the three countries, the Dutch rows will flatter the total. See our posts on Belgium and Luxembourg for those markets.
How should you build a phone stack for the Netherlands?
Keep it short, add one specialist for senior roles, and check before you dial. Here is the setup we run:
- Start with one big provider. On Dutch lists, the first provider finds most of the numbers. Kaspr found 65% usable on our Dutch rows.
- Add a cheap step that bills on hits. Tomba found 31 usable on 236 Benelux contacts for under USD 2 (October 2026). It is the cheapest per usable number we have tested.
- Add a specialist for senior roles. FullEnrich found 38 of 52 senior security mobiles in Benelux (October 2026).
- Drop numbers from the wrong country. A Belgian mobile for a Dutch contact is likely private.
- Check every number before the team dials. The first four steps fill the list. Only this one tells you who picks up.
How you order the steps and measure what each one adds is its own topic. We cover it in waterfall enrichment for phone numbers.
We cancelled Clay in April 2026. Our waterfall now runs in-house, built in Claude Code, ordered by cost per usable number.
One thing to expect. More providers means more numbers. More numbers means more wrong ones. In the Netherlands, your list will look great on paper. That is when the check matters most, because nobody questions a list that looks clean.
You can test this on your own Dutch list. Your first 100 numbers are free.
Frequently Asked Questions
Which data provider is best for the Netherlands?
No single one. In our first benchmark, every provider we saw returned 94 to 100% clean Dutch mobile formats. On senior security roles, FullEnrich found 38 of 52 in Benelux after other providers had missed them (October 2026).
What share of Dutch mobile numbers reach the right person?
In October 2026, 37 of 106 dialled usable Kaspr numbers in the Netherlands reached the person (35%). That is above the European average of about 1 in 4.
Do I need a long waterfall in the Netherlands?
Shorter than in Belgium. Kaspr found 65% usable on Dutch rows and 40% on Belgian rows (October 2026). Add one cheap step and one specialist for senior roles, then stop when steps add nothing new.
Why do Benelux lists have so many foreign numbers?
People work across borders. Luxembourg staff often carry Belgian or French mobiles. On our 461-contact Benelux list, 20 misses had only a neighbour-country mobile (October 2026).
Is Kaspr good for the Netherlands?
Yes. Kaspr returned 155 usable numbers of 239 in the Netherlands (65%), and 35% of those we dialled reached the person (October 2026). We have dialled Kaspr and Lusha numbers on our own campaigns.
What does GDPR mean for calling Dutch mobiles?
You own the accuracy of every number you call, even one you bought. GDPR asks you to keep personal data accurate, and the Autoriteit Persoonsgegevens enforces it in the Netherlands. Log which provider gave you each number. Take out neighbour-country mobiles. Remove numbers that reach the wrong person as soon as you learn it. Check local calling rules before your campaign starts.
Find the numbers, then check them
Netherlands data enrichment makes finding mobiles easy. Almost any provider gives you a clean list. But a clean list is where most teams stop looking, and two dials in three still miss.
Keep your providers. Add one for the senior roles they miss. Then check every number before your team dials it. Test 100 numbers free, no card needed. If you would rather talk it through, book a 15-minute call.