Wolters Kluwer Bluewhale Sikker E-post is a secure email and file-delivery service that enables organizations to send encrypted messages and large attachments via Outlook integration, using recipient authentication methods (SMS PIN, password, MitID) and time-limited access links.
Published Oct 15, 2026
Given the category of secure outbound email plus attachment handling, the comparison set used in this analysis is:
| Starting Price | Indicative reference: published per-month pricing available from the vendor (Denmark reference noted; Norway pricing not published) | Typically bundled within M365 licensing tiers / add-ons (varies by plan) | Published tiers vary by seats and plan (not sourced in this research) |
| Recommended for | Nordic organizations needing secure outbound email to any recipient, with Outlook-centric workflow and optional MitID/SMS flows | Organizations standardized on Microsoft 365 that require integrated encryption and policy controls | Privacy-focused organizations preferring an encrypted mailbox ecosystem and reduced recipient-side SMS dependency |
| Key Functionality | Send-secure workflow integrated into Outlook; multiple recipient authentication methods; support for large file attachments (vendor-reported upper size limits) | Deep integration with M365 identity, compliance, DLP, and auditing | Encrypted mailbox model with strong privacy positioning |
| Key Limitations | Dependency on an Outlook plugin and potential recipient friction; limited third-party review visibility; public documentation on security certifications beyond ISAE 3000 is limited | External recipient friction for some scenarios; licensing complexity and policy setup considerations | Less native Outlook integration for some workflows; integration tradeoffs and potential workflow changes for users |