Research method · Snapshot 2026-08-30

A comparison is only useful when its evidence and limits are visible.

This methodology explains how product comparisons should be scoped, sourced, dated and corrected. It does not declare an unsupported “best” provider.

Evidence hierarchy

Tier 1

Primary official evidence

Regulator publications, numbering administrators, provider documentation, current terms and dated rate sheets.

Tier 2

Reproducible observation

Dated product-interface or support-flow observations with scope and account context recorded.

Tier 3

Qualified secondary evidence

Reputable analysis used for context, never to override a newer primary source.

Evaluation criteria

  • Number countries and types, verified at number level
  • Inbound and outbound voice context
  • SMS/MMS eligibility and registration
  • Emergency-calling setup and limitations
  • Routing, hours and voicemail workflow
  • Desktop and mobile administration
  • Portability prerequisites
  • Rate components and quote date
  • Support path and documentation quality
  • Privacy, security and compliance claims

Snapshot dates and change control

Every comparison should show when each source was checked. Dynamic inventory, capabilities and prices must be described as a snapshot, not a permanent fact. Material changes require a new review date and, where appropriate, an archived prior statement.

Limitations

A public comparison cannot reproduce every account, negotiated term, country, number, destination or workflow. Absence of a documented feature is not proof it does not exist. Availability should be confirmed directly for the intended use.

Corrections process

  1. Submit the challenged statement and source through the existing contact page.
  2. Provide a primary or reproducible dated reference.
  3. We compare source dates, scope and product context.
  4. Confirmed corrections update the statement, citation and review date.