Most people asked to "get a list" start by looking for one to buy. Below: the alternative: three steps that produce a shorter list, with fewer bounces and a reason to write behind every row. It also covers what each row needs and the EU and Czech rules.
What is a lead list?
A lead list is a working table: one row per person you intend to contact, grouped by company. It is the input to every outbound sequence, call block or ad audience. Review sites such as G2's sales intelligence category treat list building as a core feature of the tools in that category.
A list is not a database. A database holds everyone. A list is a selection from it, made for one campaign and one message.
What should every row contain?
Every row needs four things: who the company is, why it fits, who the person is with a working contact, and why now. The template below has twelve columns covering them.
| Column | Example | Why it is there |
|---|---|---|
| Company | Northwind Logistics | Grouping, deduplication |
| Domain | northwind.example | Matching to CRM and blacklist |
| Fit field | Sales team of 12 | The fact that makes it relevant |
| Fit verdict | Keep | Result of the classification |
| Person | Jana Example | Who receives the message |
| Role | Head of Sales | Matches message to responsibility |
| jana@northwind.example | Channel one | |
| Email status | Verified | Avoids bounces |
| Phone | Direct number or empty | Channel two |
| Signal | Hiring two SDRs | The trigger for writing |
| Signal date | October 2026 | Shows whether the trigger is still fresh |
| Reason for outreach | Scaling outbound, likely short on data | The first line, in one phrase |
All values are illustrative.
How do you build a list without buying one?
Build it in three steps, each one narrowing the previous result.
- Seed with lookalikes. Describe your ideal customer in plain text, or give a handful of companies you already sell to. Leadspicker's guidance is that a sample of existing customers is usually the stronger seed, because it encodes things about your ideal profile you would struggle to put into words.
- Enrich the result. Add the fields that decide relevance: department sizes, the company's own description, technologies, open job ads.
- Classify with an AI column. Write your criteria as a prompt and let the column mark each row keep or drop. Then find and verify contacts only for the rows you keep.
Worked example, illustrative: a seed of five customers returns a few hundred similar companies. Enrichment shows which have a sales team above ten people and are hiring for sales. The AI column keeps the ones that match. Contacts are found only for those, so you pay for finding and verifying the rows you will actually write to.
Two public positions shape what a list may contain. The Czech data protection authority ÚOOÚ answers, when asked whether a purchased company database can be used for commercial messages, 'practically, it is not possible' (question 11 of its FAQ on Act 480/2004). Spamhaus treats purchased, rented or harvested lists as a breach of good sending practice.
Why is a shorter list usually better?
A shorter list is cheaper to send, safer for your domains and easier to work properly. Volume has a hidden cost: the sending infrastructure. Leadspicker's knowledge base notes that teams who want to reach 20,000 to 30,000 leads a month rarely price in what it requires: hundreds of mailboxes across dozens of domains.
People are a limit too. The Bridge Group's 2025 SDR report puts typical activity at around 112 a day per rep. A list larger than your team can follow up is a list where replies wait and signals expire.
The opposite mistake exists. A list so small that a few percent reply rate yields no meetings gives you no data to judge the campaign. Aim for enough rows to read a result, and no more.
What are the rules for lists in the EU and Czechia?
In the EU, B2B cold outreach is usually handled under legitimate interest under the GDPR. Leadspicker's knowledge base stresses that legitimate interest is not a blanket permission: the outreach has to be proportionate and relevant to the recipient's professional role. A narrow, relevant list is easier to justify in that balancing test.
Bought lists are the weak point. The Czech data protection authority, ÚOOÚ, answers the question of whether a purchased company database can be used for commercial messages with "practically, it is not possible" (question 11 of its FAQ on Act 480/2004). Deliverability rules point the same way: Spamhaus sender guidelines rule out purchased, rented and harvested lists.
Leadspicker precomputes its whole database into lookalikes, so a list can be seeded from a plain-text description or from a sample of existing customers, and then narrowed with enrichment.
Frequently asked questions
What should a lead list contain?
For each row: the company, the field that makes it fit, the person and their role, a verified email or phone number, and the signal or reason for writing now. Without the reason, the row is a contact, not a lead.
What rules apply to a bought lead list in the EU?
The rules apply to how the list is used. Under the GDPR, outreach usually relies on legitimate interest, which needs a balancing test. Asked whether a purchased company database can be used for commercial messages, the Czech authority ÚOOÚ answers 'practically, it is not possible' (FAQ question 11).
How many leads should a list have?
Enough to read a result, and no more than your team and sending setup can handle. Large lists need large infrastructure, while very small ones produce too few replies to judge the campaign.
- The Bridge Group, 2025 SDR Models and Metrics Report
- G2, Sales Intelligence category
- ÚOOÚ, Frequently asked questions on Act No. 480/2004 Coll. (in Czech)
- Spamhaus, Sender Guidelines
- GTM playbook for 2026 by Leadspicker, chapters: Lookalikes, Enrichment, Sending volume and domain rotation, legal basis for cold outreach
