How does an SME stay tax-compliant in 70 countries?

Short answer

Staying tax-compliant across 70 countries means each invoice follows the format, the mandatory content and the transmission channel of its market — not a generic PDF.
4b2b.net includes the local e-invoicing formats and channels of every open market, plus VIES validation for intra-EU VAT numbers.
Each market has its own rules on VAT treatment, mandatory fields and retention, and the ecosystem applies them from the market you select.
Without an integrated ecosystem, the same coverage takes a separate module or local tax advice in every country.

The document format differs: each market defines its own electronic invoice structure.
The channel differs: some countries require a state platform, others use a network such as Peppol.
Filing and retention periods are set separately in each jurisdiction.
The place-of-supply rule decides whether the invoice carries local VAT or is reverse-charged.

In United States, reporting duties follow IRS rules, and the invoice has to support them.
Where an electronic channel applies in United States, documents go through voluntary e-invoicing exchange over the DBNAlliance network and state sales-tax filing in the required format, not as an attached PDF.
The identifying details of both parties must match what is recorded with the Secretary of State.
For intra-EU supplies, the customer's VAT number is checked in VIES before the invoice is issued.

Example: a company in United States sells services to a business in another country — the ecosystem issues the invoice in the format that market requires, with the correct VAT treatment.
Example: an owner invoices a customer abroad and the document is sent through that market's official channel automatically, with no manual upload.

Sending a generic PDF to EU customers — in several member states an invoice without the local format is not valid for tax purposes.
Applying your own VAT rate to services supplied abroad; the place-of-supply rule differs by type of service.
Archiving invoices in a house format instead of the format in which they were issued.

Per-market compliance applied automatically once the customer's country is selected.
The document is generated in the format the selected market requires, ready for that market's official channel.
VIES validation included before an intra-EU invoice is issued.
Digital archiving in the format required locally, ready for an audit.
Multi-market reporting from one panel instead of six systems.