How to fill in your organization's tax details (DIAN)

In Settings → DIAN you register the tax details the DIAN identifies your organization by. These details travel on every invoice you issue.

They must match your RUT exactly. If they do not, the DIAN may accept the invoice with an observation, or reject it outright.

Before you start

Have your RUT open. Every field on this screen comes from it.

The fields, one by one

Tax ID (NIT) : Digits only — no check digit, no dots or dashes. Example: 900123456.

Check digit : You do not type it. We compute it from the NIT and show it beside it. For NIT 900123456 the digit is 8. If your RUT shows a different one, the NIT was mistyped.

Legal name : The full legal name as it appears on the RUT — not the trading name.

Tax regime : One of three: IVA responsible (most clinics), not IVA responsible (independent professionals who do not charge IVA), or large taxpayer (only if the DIAN classified you so by resolution).

Economic activity (CIIU) : The four-digit code for your main activity, from the RUT. Example: 8621.

Municipality (DANE code) : The five-digit code for the municipality of your tax domicile. Example: 11001 (Bogotá D.C.).

Address, Phone, Email : As registered on the RUT. Invoices are delivered to that email address, so use one somebody reads daily.

If it will not save

We check every field before sending anything to the DIAN. That is deliberate: a malformed value does not fail here, it fails later — the DIAN rejects all your invoices with a message that never names the offending field.

MessageWhat it means
The check digit does not match the NITThe NIT was mistyped. The digit is arithmetic on the NIT, so if it disagrees, the NIT is what is wrong.
The NIT must contain only digitsA letter or a space survived.
The economic activity (CIIU) is 4 digitsYou typed the code with dots, or pasted the description instead of the number.
The municipality is the 5-digit DANE codePick it from the list. The RUT prints the department and the municipality separately; the DANE code joins them: department 05 + municipality 266 = 05266.

Tip

You do not need to upload a digital certificate. DeusRex signs your documents through its authorized provider under a mandate agreement.