Paraguay: the SIFEN is phasing in electronic invoices
In Paraguay, per the sources read, the tax authority DNIT (formerly the SET) runs the SIFEN, the national electronic invoicing system, and brings taxpayers in by group on dates set in resolutions. Below: how it works as vendor guides and press report it, where the sources are thin, and a local check of a RUC’s check digit.
How it works (as vendor guides, press and the authority report)
| Step | What happens |
|---|---|
| Identify | The issuer has a RUC: a base number (a cédula for people, 8 digits starting 80 for companies) and a check digit after a hyphen. |
| Issue a document | The issuer produces an electronic document (DE, such as an invoice) as signed XML in DNIT’s format and sends it to the SIFEN for approval (vendor guides; the technical manual is unread). One guide describes a 44-digit control code (CDC) on each document. |
| Deliver | The buyer receives the document, usually as a printable representation (KuDE) with a QR code, per vendor guides. |
| Verify | DNIT has a public RUC lookup at dnit.gov.py; this page does not use it. |
Dates as reported by press (ABC Color, May 2026) and a vendor calendar: groups start on 1 June 2026, 1 September 2026, 1 December 2026, 2 March 2027, 1 June 2027 and 1 September 2027; suppliers to the State from 2 January 2026. Where it is unsettled: the resolution itself (RG 52) was not read, the number of the State-supplier rule differs between sources (RG 41/2025 or RG 21/2024), the legal base is said to include Decree 872/2023, and which group a given company is in must be checked with DNIT. No penalty is stated because none was read. A summary, not tax advice.
Check a RUC
Tests the shape (5 to 9 digits and a check digit; spaces, dots and hyphens are ignored) and the check digit. It does not look anything up, so it cannot say whether the RUC is registered, active, or belongs to the name on the invoice.
The rule (digits of the base weighted 2,3,4,… from the right, back to 2 after 11; the check digit is 11 minus the sum mod 11, or 0 when the remainder is 0 or 1) is the one open-source implementations and vendor validators describe. It was not read from DNIT’s specification, and no registered RUC with a confirmed digit was reachable, so the sample (80016875-5) was computed by hand and may not be a registered RUC.
What this checker does and does not cover
The main checker reads UBL, CII and Factur-X and applies EN 16931 and Peppol rules. It does not call DNIT’s service, cannot obtain or verify an approval, and has no DNIT schema or codes. Treat the RUC test here as a typo catch only.
Test a file before you send it
For a European or Peppol invoice, open the checker, drop your XML and read the findings, each with a rule ID and a fix (the rule reference). No account, nothing uploaded. No invoice yet? The e-invoice creator turns a form into UBL or CII XML and checks it. Other countries: all side by side Mexico Brazil Chile Colombia Peru Argentina Uruguay.
Common questions
What is the SIFEN?
The Sistema Integrado de Facturación Electrónica Nacional, run by the tax authority, DNIT (formerly the SET). Issuers send electronic documents (DE) in DNIT’s XML format for approval, and one vendor guide describes a 44-digit control code (CDC) on each. This is a summary from vendor guides and press, not advice; confirm with DNIT or your accountant.
Who has to issue electronic invoices?
Press reports say a DNIT resolution (RG 52, read only through news excerpts) named new issuers in six groups with start dates from 1 June 2026 to 1 September 2027, and that suppliers to the State must issue electronically from 2 January 2026. Sources disagree on which resolution number sets the State rule (RG 41/2025 or RG 21/2024), and the dates were not read in the resolution itself, so check dnit.gov.py.
What is a valid RUC?
A base number and a check digit that follows from it by a mod 11 rule. A matching digit does not mean the RUC is registered or active; DNIT’s public register answers that. The test on this page catches typos only.
Can this checker validate a Paraguayan invoice?
No. It does not read DNIT’s XML schema and cannot obtain or verify an approval. It does test a RUC’s shape and check digit on this page, and a clean result is not an approval by DNIT.
Open the E-invoice Preflight checker to validate your own invoice file.
More countries
Australia Austria Belgium Brazil Bulgaria Croatia Cyprus Czech Republic Denmark Estonia Finland France Germany Greece Hungary Ireland Italy Latvia Lithuania Luxembourg Malta Netherlands Nigeria Norway Poland Portugal Romania Serbia Singapore Invoicenow Slovakia Slovenia Spain Switzerland Uk India Malaysia Saudi Arabia Sweden Turkey United Arab Emirates Peru Chile Colombia Uruguay Vietnam