Business Data Sources:
where the information that sells lives

Q: Is it legal to use business data for prospecting?

Yes, as long as the data comes from public sources and complies with data protection regulations (GDPR in Europe, for example). Business registry and public directory data are legal for commercial use.

Not all sources are equal. Some give data, others give opportunities.

B2B Data·March 2026·5 min read

Key Takeaways

3 source types: registries, directories, and data platforms
Official registries are accurate but lack contact data
The best source cross-references multiple origins for complete data

The Challenge

The problem isn't lack of data. It's quality

In 2026, the amount of available business data is enormous. Business registries, industry directories, online platforms, professional social networks. The real problem is that most of these sources are incomplete on their own.

A business registry gives you the legal name and tax ID, but no email. A directory gives you the phone, but you don't know if the company is still open. According to Eurostat, 25% of European SMEs change or close within their first 3 years. If your business database depends on a single source, it's destined to become obsolete.

62%

of single-source data is incomplete

25%

of SMEs change or close within 3 years

more accuracy when cross-referencing sources

Comparison

The 3 families of data sources and what to expect from each

Each source type has strengths and weaknesses. Understanding them helps you know where your data comes from and why some works for selling and some doesn't.

Official registries

Fiscal and legal data

Business registries, tax authorities, chambers of commerce. Available in most countries (Companies House in UK, SEC in US, Registro Mercantil in Spain).

+ Reliable legal data

- No email, website, or phone

Public directories

Business listings

Yellow pages, industry guides, business maps. Cover many countries and sectors, but data quality varies widely.

+ Wide local coverage

- Frequently outdated data

B2B platforms

Cross-referenced and enriched data

Combine multiple sources, verify, and enrich. Offer email, phone, website, geolocation, industry, and more.

+ Complete and actionable data

- Require subscription

The ideal source doesn't exist as a standalone product. What works is a platform that combines, cross-references, and verifies data from multiple origins, eliminating duplicates and filling gaps automatically.

Access cross-referenced data from multiple sources

MapiLeads combines registries, directories, and public data to give you the most complete business database in any industry and country.

Generate Database Free

Criteria

5 things to demand from any data source

Real contact data

Verified email and phone. A database without contact data is a decorative directory. You need to be able to contact businesses directly.

Frequent updates

Data from 2 years ago is garbage. Demand regular updates and verification dates. 30% of B2B data expires every 12 months.

Global coverage

If you sell internationally, you need sources covering multiple countries: Spain, Mexico, USA, Germany, Brazil, UK, and more. Not just local markets.

Segmentation filters

Being able to filter by industry, size, location, and business type is essential. Without filters, you have a pile of useless data. With them, you have a segmented database.

Legal compliance

Make sure data complies with GDPR (Europe), CCPA (US), and local regulations. Non-compliant sources can expose you to penalties.

Benchmark

What data does each source type provide?

Data Point	Official registry	Directory	B2B Platform
Company name	Yes	Yes	Yes
Contact email	No	Sometimes	Yes, verified
Phone	No	Yes (sometimes old)	Yes, updated
Industry/activity	SIC/NAICS code	Basic category	Industry + subcategory
Geolocation	Fiscal address	City	Lat/lng + map
Website & social	No	Partial	Yes, with links

The best source isn't the one with the most data. It's the one with the right data

All the data you need, from one source

MapiLeads cross-references official registries, directories, and public data from any country to give you complete, verified business databases. No searching 10 different places. See plans or contact us.

Generate Database Free

Frequently Asked Questions

What is the most reliable business data source?

It depends on the use case. Official registries have accurate fiscal data but lack contact details. B2B platforms combine sources for complete coverage. See MapiLeads features.

Is it legal to use business data for prospecting?

Yes, as long as data comes from public sources and complies with data protection regulations (GDPR in Europe). Business registry and public directory data are legal for commercial use.

How many data sources should I use?

Ideally, use a platform that already combines and cross-references multiple sources. This eliminates the manual work of cleaning and unifying data from different origins.