From the Mailsource team
Blog
Ideas, strategy and results on personal B2B outreach
Posts
Cold Email, PECR and UK GDPR: Why B2B Letters Are the Legally Safer Outreach Channel
Cold B2B email in the UK sits under PECR and UK GDPR, and the rules are stricter than most founders realise. Here's where cold email creates risk — and why a well-run letter campaign sidesteps most of it.
Read moreHow to Track ROI on B2B Direct Mail: QR Codes, Landing Pages & Attribution (2026 UK Guide)
"You can't track direct mail" stopped being true years ago. Here's how UK B2B teams use QR codes and dedicated landing pages to measure direct mail like any digital channel — scans, conversions, cost-per-lead, all of it.
Read moreDo Letters Still Work in Marketing? The Honest 2026 Answer for B2B
Letters aren't dead — they're outperforming email on response rate. Here's the real 2026 data on direct mail costs vs. engagement, where B2B letter campaigns fail, and how Mailsource fixes them.
Read moreThe UK B2B Market in One Page (And How to Stop Spraying and Praying)
5.7 million UK businesses, broken down fast — plus why 'find your market' isn't the hard part. The real problem is narrowing it, and how Mailsource's AI heuristics do it for you.
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