Between 31 August 2026 at 06:00 UTC and 2 September 2026 at 13:00 UTC, sales tax was not applied to some invoices created on Subbly. The cause was an upstream unexpected failure at TaxJar, the provider we use to calculate tax rates, which our system did not surface. Affected invoices were charged without the tax that should have applied. We have now corrected those invoices, collected the missing tax where it was owed, and notified everyone affected.
During this window TaxJar began returning 403 errors to our tax calculation requests without warning. Our billing engine treated a failed calculation as "no tax", built the invoice with a zero tax amount, and charged the customer the untaxed total. Because the failure was handled silently, no alert reached our team. We learned of the problem when it was reported to us, at which point the underlying TaxJar errors had already stopped.
Only shops that rely on Subbly's own TaxJar integration were affected. Shops with their own TaxJar account, and shops with tax-inclusive pricing, did not undercharge their customers.
We identified every invoice created in the window that was missing tax and recalculated what the tax should have been, using the same calculation the original renewal or checkout would have used.
For shops with tax-exclusive pricing, we charged the missing tax to the customer's payment method on file as a separate, clearly labelled sales tax invoice, and recorded the tax on the original invoice and order. Each of those customers received an email from the shop explaining the charge. Where a charge could not be collected, the shop owner has been told which customers were affected so they can decide how to follow up.
For shops with tax-inclusive pricing, customers had already paid the correct amount, so we only recorded the missing tax breakdown on the invoices and orders. No charge was made and no customer email was sent.
Every affected shop owner received a summary of exactly what was done for their store.
A failed tax calculation is no longer silent. Our team is now alerted immediately when the tax provider returns errors, so a problem like this would be caught within minutes rather than days.
We are also working on fallback strategies for tax calculation, so that an upstream outage does not result in invoices being charged without tax.
We are sorry for the inconvenience this caused you and your customers. We know an unexpected charge, however small and however well explained, is not something anyone wants to receive from a store they trust. And your trust in us as a platform is taken very seriously. If you have any questions about the affected invoices, the corrections we made, or the steps above, please reach out to us through the support chat in your admin and we will help.