B2B cold email in Spain: a practical guide

August 13, 2026 · The Vakenlab team

B2B cold email is still the cheapest channel for opening sales conversations between companies. It's also the easiest to get wrong: a domain burned by sending too much too soon takes months to recover, if it recovers at all. This guide covers how we run it at Vaken for companies selling in Spain: infrastructure first, writing second, compliance always. And if you're still choosing a channel, start with what B2B meetings cost to book through each route: yourself, an SDR, an agency, or agents.

What B2B cold email is (and how it differs from spam)

A B2B cold email is an individual sales email, sent to a specific person at a specific company you've had no prior contact with, because there are observable reasons to think your offer is relevant to them. The difference from spam isn't cosmetic, it's structural: spam is massive, impersonal, and indifferent to the recipient; a well-made cold email is scarce, researched, and relevant to the role that receives it.

That difference changes everything: deliverability, response, and how the rules apply.

The legal side, without the smoke

In Spain, commercial email sits between two sets of rules: the GDPR (personal data protection) and the LSSI, Spain's law on information society services. In B2B, serious practice rests on four criteria:

• Legal basis and relevance: write only to roles for which your offer relates directly to their job.
• Data minimization: use only the essential professional data, from legitimate sources, not personal dossiers.
• Transparency: make clear who's writing, from which company, and why.
• Easy objection: a simple way to say "stop writing to me," and a log that guarantees it sticks.

Two honest warnings. First: this is a summary of practice, not legal advice; your specific case (industry, data types, list origin) deserves its own review. Second: anyone telling you "anything goes in B2B" is gifting you their risk.

Infrastructure comes before the emails

The most expensive cold email mistake happens before the first line gets written: sending from your company's main domain, unprepared. What a serious system does instead:

• Separate sending domains: prospecting goes out from sibling domains, not the domain you invoice and serve clients from. If something goes wrong, your operational email isn't dragged down with it.
• Full authentication: SPF, DKIM, and DMARC configured before the first send. Without it, the filters don't even evaluate you: they discard you.
• Warm-up: weeks of gradual activity so the domain earns reputation. It can't be compressed without paying the price.
• Gradual volume: few emails per mailbox at first, increasing only if the signals (bounces, complaints, replies) hold up.

How to write a cold email that gets replies

With the infrastructure in place, the writing decides. What we see work, email after email:

• Short: under a hundred words. The recipient decides in seconds whether to keep reading.
• Real context: a first line that proves you know who they are and why you're writing to them specifically. If the line would fit any company, it doesn't fit.
• One ask: usually a short call. No attachments, no three links, no catalog.
• Paced follow-ups: most replies come from follow-ups, not the first touch. Two or three, spaced out, each adding something new, then stop.

The mistakes that burn domains

The five we've most often seen kill an entire channel:

• Buying bulk lists. Old data, spam traps, and recipients with no connection to your offer. The shortcut with the highest price tag.
• Full volume from day one. Hundreds of emails from a brand-new domain reads as a spam confession to the filters.
• The same template with the name swapped. The filters detect the pattern, and so do the recipients.
• Ignoring opt-outs. Beyond the legal risk, every later complaint weighs on the domain's reputation.
• Measuring opens. Optimizing an unreliable metric leads to gimmicky subject lines and conversations that never happen.

All five are avoidable and all five are common. If you recognize any of them in your current operation, stop it before you scale the problem.

How Vaken does it

At Vaken, cold email is run by the cold outreach team: five agents with one job each. Skriv ("write") drafts every email with the recipient's context; Takt ("beat") paces the follow-ups; Skjold ("shield") looks after the sending domains and deliverability; Svar ("reply") reads every response and decides the next step; and Møte ("meeting") locks the slot on your calendar. Before every send, Lov ("law") reviews compliance. The whole system, warmed dedicated domains included, is in the €499 per month plan.

If you want to understand what a system of agents like this can and can't do, we lay it out without the smoke in this article.

Frequently asked questions

Is it legal to cold email companies in Spain?

It can be, when it rests on a proper legal basis, messages relevant to the role, clear identification, and easy objection. The GDPR and Spain's LSSI set the playing field, and the specific case deserves its own review: this guide is practice, not legal advice.

How many emails per day?

Few, at first. Standard practice is to start with low volumes per mailbox and ramp up over weeks as the domain's reputation grows. The exact number matters less than the direction: gradual always, massive never.

Should I buy a contact list?

No. They mix old data, spam traps, and people with no connection to your offer. Your own list, built company by company from your buyer profile, gets more replies at less risk.

Which metric do I watch: opens or replies?

Replies and meetings. Opens are less and less reliable because of privacy protections in email clients, and no open has ever paid an invoice.

What do I do with opt-out requests?

Immediate removal, an objection log covering every mailbox, and a polite reply if appropriate. A well-handled opt-out is the system working, not a failure.