Visas & MovingUpdated 2026-10-11 · 7 min read
CUIL in Argentina for UK Citizens: CUIL vs CDI
A CUIL is the free employment and social-security identifier used by Argentine employees and residents. A non-resident buying property commonly needs a CDI from ARCA; someone invoicing in Argentina needs CUIT registration.

In short
- ANSES assigns a CUIL free of charge for employment and social-security records.
- A current residencia precaria can support a provisional CUIL before the DNI arrives; tourist admission alone cannot.
- ARCA's CDI identifies someone without CUIL or CUIT for a limited transaction, often a non-resident property purchase.
- Argentine invoicing requires CUIT registration and the appropriate tax status, even if the person already has a CUIL or CDI.
- After the DNI arrives, ANSES can unify a provisional CUIL with the definitive identity record.
An Argentine employer asking for your CUIL needs a number that connects your pay and social-security contributions to your identity. A British property buyer who still lives in the UK may instead be asked for a CDI for the deed. Both identifiers are free, but the reason for obtaining one determines which agency handles it. Anyone planning to invoice Argentine clients needs a CUIT tax registration.
Which number fits the activity?
CUIL (Código Único de Identificación Laboral) is roughly comparable to a UK National Insurance number, although it is used more widely by Argentine employers, banks and public services. ANSES, the social-security agency, issues it. ARCA, the tax and customs agency formerly called AFIP, handles CUIT for taxable activity and CDI (Clave de Identificación) for a person without CUIL or CUIT who needs to complete a limited formal or tax-related transaction. RENAPER handles the DNI, the identity document issued to foreign residents.
| Identifier | Usual holder and purpose | Issuer | Official fee (confirm on the issuer's page) |
|---|---|---|---|
| DNI | Foreigner granted residence; identity document, not tax registration | RENAPER | Check the current RENAPER charge for the DNI application |
| CUIL | Employee or resident using employment and social-security services; not authorisation to invoice | ANSES | ARS 0 / US$0 |
| CUIT | Freelancer, monotributista, business or other person with taxable activity; not immigration status | ARCA | ARS 0 / US$0 |
| CDI | Person with neither CUIL nor CUIT needing a limited transaction; not a work permit or general tax registration | ARCA | ARS 0 / US$0 |
The three work or tax numbers can look identical in format. Use the full number exactly as issued; do not infer personal details or create a second registration from its prefix. A number itself grants neither residence nor permission to work: Migraciones handles those questions.
Starting an Argentine job before the DNI arrives
Employers use a CUIL to register salary, pension contributions and obra social, employment-linked health cover. Argentine banks and Mi Argentina services commonly ask residents for it too. A UK National Insurance number cannot fill that role. A 90-day visitor admission alone does not provide the residence basis for a CUIL, so prospective employees need the appropriate immigration route; see Argentina visa and residence routes.
After a qualifying residence application, Migraciones normally issues a residencia precaria, proof of pending status. ANSES can assign a CUIL provisorio against a UK passport and current immigration document while the DNI is pending. A booking receipt for a future application is different from the precaria. ANSES's current foreigner procedure and appointment channel determine where the original passport and immigration document, with copies, are presented. Assignment is normally completed in the interaction once identity data are accepted, but there is no guaranteed wait or correction time.
Names are where the process often slows down. The constancia, ANSES's free PDF proof of the CUIL rather than a plastic card, should show the passport name and birth date correctly; hyphens, two surnames and middle names can create mismatches. The number itself has no expiry date. ANSES charges nothing for assignment, although a private gestor may charge to resolve an administrative problem.
When RENAPER issues the DNI, a definitive CUIL is normally linked to it. The ANSES constancia service accepts the details as printed on the DNI and provides a downloadable PDF to give an employer or bank. If the service cannot find the record or shows an error, the ANSES office finder gives the current appointment route; the original DNI and a civil document supporting the correction may be needed. If the definitive number differs from the provisional one, ANSES can unify the two records using the DNI, passport and both constancias so earlier salary and contributions stay together. The DNI guide for UK citizens covers the residence-to-card stage.
The CDI for a buyer who remains abroad
A Bristol resident buying a Buenos Aires flat before moving is a typical CDI case. The escribano, Argentina's civil-law notary, needs an identifier on the deed, while a property purchase alone does not turn the buyer into an employee or freelancer. The CDI is for someone with neither CUIL nor CUIT. A buyer who already has a CUIL, or plans taxable activity, may need the appropriate CUIT route instead; the escribano can identify which registration the transaction requires. Ask the bank separately which identity, address, residence and source-of-funds evidence it requires; a CDI alone does not settle account eligibility.
The CDI application uses Form F.663 from ARCA's official service, marked Solicitud. Its current instructions set the rules for copies and signature certification. Applicants present passport and the identity and domicile evidence applicable to their circumstances through ARCA's stated appointment or filing channel. A representative needs an acceptable poder especial (specific power of attorney); a UK-executed power normally needs an FCDO apostille and certified Spanish translation. Older forms or advisers may still call the agency AFIP; use ARCA's current instructions.
ARCA charges nothing to assign a CDI. Its published procedure mentions up to 30 administrative working days for non-residents; confirm the timing applicable to your filing rather than promising a deed date. Unclear passport, address or representative documents can require further evidence, which matters if a deed has a proposed completion date. The issued CDI constancia goes to the escribano and remains useful when the buyer's status later changes: ANSES or ARCA can link or regularise existing records rather than generating duplicates. The British buyer's property guide sets out the wider purchase sequence.
When the buyer later starts invoicing
Suppose Sarah buys the Buenos Aires flat while living in Bristol, without a DNI, CUIL or CUIT. Her escribano confirms a CDI is needed and she files F.663 through a representative appointed under an authenticated power. ARCA's CDI fee is ARS 0; notarial, apostille and translation work are separate costs.
Eight months later she moves under temporary residence, receives a DNI and begins invoicing design clients. The taxable work calls for a CUIT, appropriate tax status and clave fiscal, with the existing CDI disclosed to ARCA. She also checks her ANSES identity record. Do not assume that having an identifier completes a tax registration: the activity and agency registration matter. The CUIT is the number that identifies people with tax obligations, whereas a CDI is for a limited transaction and does not itself satisfy any filing duty. The CUIT and clave fiscal guide covers that registration.
A mismatched name between passport, precaria, DNI and agency records is best corrected at the source before an employer registers pay or an escribano completes a deed. The free identifier is often the quick part; the underlying immigration status, tax registration and document evidence determine what the person can actually do.
Questions
- Can a UK citizen get a CUIL in Argentina without a DNI?
- ANSES can assign a provisional CUIL using a passport and suitable Migraciones proof such as a current residencia precaria. Tourist admission alone is insufficient; once the DNI arrives, the ANSES records can be checked and unified.
- What is the difference between CUIL and CDI in Argentina?
- ANSES issues CUIL for employment and social-security identity. ARCA issues CDI to someone without CUIL or CUIT for a limited transaction such as a non-resident property purchase.
- Is a CUIL the same as a CUIT?
- CUIL identifies someone in employment and social-security systems; CUIT is the tax registration for invoicing and business activity. Taxable activity still requires the appropriate ARCA registration; do not infer it solely from an identifier's appearance.
- How much does a CUIL or CDI cost in Argentina?
- The official ANSES CUIL and ARCA CDI assignment fees are both ARS 0; confirm on each agency's page before relying on that. A representative, notary, apostille or translator may still charge for related work.
- Does a CDI let a foreigner buy property in Argentina?
- A CDI provides the identifier commonly needed on a non-resident buyer's deed. The escribano also examines title, identity, representation and source of funds; special land restrictions can apply beyond an ordinary urban purchase.
Official sources
- TEXTO ACTUALIZADO - Ley 25871 - MIGRACIONES | Argentina.gob.ar
- Radex | Dirección Nacional de Migraciones
- Solicitar constancia de CUIL | Argentina.gob.ar
- Obtener la clave de identificación - CDI | Argentina.gob.ar
- Obtener CUIT por internet | Argentina.gob.ar
- Get your document legalised: Overview - GOV.UK
- Voluntary National Insurance: If you live or work abroad (or have previously) - GOV.UK
- Voluntary National Insurance contributions abroad from 6 April 2026 - GOV.UK
- Obtener una residencia temporaria por reunificación familiar | Argentina.gob.ar
- Entry requirements - Argentina travel advice - GOV.UK
- Legalizaciones - CTPCBA - Colegio de Traductores Públicos de la Ciudad de Buenos Aires
- Consulado General en Londres | Poderes y Escrituras Públicas
- TEXTO ACTUALIZADO - Ley 26994 - CODIGO CIVIL Y COMERCIAL DE LA NACION | Argentina.gob.ar