Methodology: how the figures are sourced and verified
Every load-bearing number on this hub — a platform fee, a VAT threshold, a tax rate — is either verified against a primary source with a real date, or explicitly labelled as an assumption. The guides print both dates at the top of the page (“Last updated” for the prose, “Data verified” for the figures), and the hub-wide verification date (2026-06-12) is printed in the footer of every page.
Primary sources only
- Platform fees (Gumroad): the platform’s own published pricing at gumroad.com/pricing — never blog posts or fee-comparison roundups. The distinction between the platform fee (10% + $0.50) and the card-processing line (2.9% + 30¢) comes straight from that page.
- EU VAT rules (OSS): the European Commission’s VAT One Stop Shop portal and its VAT e-commerce pages; VAT-number validation via VIES.
- Per-country freelance tax rates: the day-rate calculator carries a versioned dataset (v2026.06) where every country row cites its national tax authority — HMRC, Bundesfinanzministerium, URSSAF, Agenzia delle Entrate, Agencia Tributaria, Portal das Finanças, Belastingdienst, the Polish MF, ANAF, and Revenue.ie — with the dataset’s own verification date printed in the tool.
Assumptions are labelled, not laundered
Some inputs have no publishable source: platforms do not publish refund rates, and nobody audits a freelancer’s billable-day count. Where a worked example needs such a number, the guide says “assumption” in the same sentence — the 6% refund allowance in the margin example and the ~150 billable days in the day-rate example are the two standing cases. We do not dress assumptions up with fake citations.
Verification dates are real, not decorative
A “Data verified” date only changes when a human re-checks the figure against the cited source. Pages that have not been re-verified keep their older date visibly — we do not bump dates to look fresh. Known upcoming changes are stated next to the figure they affect (for example, the EU VAT changes scheduled for January 2027 that will alter how the €10,000 OSS threshold is tracked).
Staleness is surfaced, not hidden
The hub declares a staleness threshold of 30 days. When the verification date exceeds it, the guides badge their content as needing re-verification instead of presenting it with false confidence; the footer date tells you where the clock stands on any page.
Corrections
Found a figure that disagrees with its cited source? Write to [email protected] with the page URL and the source link. Corrections ship with a fresh verification date — the fix and its provenance stay visible.
See also: about this project and the tools directory.