Social Security & Cross-Border Rights
Planned treatment abroad: what to do if the CNS refuses authorisation
A procedure is planned abroad, but you receive a CNS refusal. Before confirming costs or resending the same documents, identify what was refused: prior authorisation, the coverage framework or a reimbursement already requested. These situations require different steps.
Check the treatment and regime concerned
The CNS distinguishes countries and care categories. Certain treatment, particularly hospitalisation with an overnight stay, requires prior approval. Sending an application does not amount to approval. [1] Gather the prescription, quotation, planned establishment, dates and response received.
Also check whether your situation genuinely concerns transfer for planned treatment. Necessary care during a temporary stay and care in a cross-border worker’s country of residence may follow other rules. Specify affiliation and residence from the outset rather than treating a European card as an answer to every situation.
Address the refusal’s reason
The application must be medically justified. [1] Have the decision reviewed by the doctor organising treatment. Ask them to clarify evidence addressing the reason given: nature of care, justification for referral, timing and useful medical documents.
A more detailed quotation may resolve unclear pricing, but not necessarily a medical issue. Conversely, a new medical report does not always clarify the establishment’s identity or type of procedure requested. Classify the questions to provide a targeted reply.
Prepare a chronology: initial application, supplementary documents, refusal, notification date and proposed treatment date. Keep the envelope and acknowledgements. If treatment is imminent, flag that constraint without assuming it alters appeal rules.
Preserve the challenge within the relevant deadline
For the prior-approval refusal described by the CNS, the challenge to its board of directors must be signed and sent by registered letter within forty days after notification. [1] Check the recipient and instructions in your decision; a simple request for an explanation should not be presumed equivalent to this appeal.
Any subsequent stage falls within the social security courts’ framework. [2] Have the decision received after the challenge and its remedies assessed, rather than applying the first deadline indiscriminately at every stage.
Check the cost even if approval is obtained
The CNS distinguishes in particular S2 approval from approval under the cross-border healthcare directive. Payment arrangements differ; authorisation does not guarantee reimbursement of the entire invoice. [1] Request a written explanation of coverage and possible remaining costs.
- Obtain confirmation that the establishment and procedure match the approval.
- Check validity before changing the treatment date.
- Identify advances, supplements and ancillary services in the quotation.
- Keep billing documents and proof of payment.
Avoid irreversible financial commitments based solely on a telephone exchange. KM Legal can assess the refusal, dates and supporting documents to prepare a challenge suited to your situation, alongside the necessary medical explanations.
Frequently asked questions
Is filing my application enough to travel for treatment?
Where prior approval is required, the CNS states it must be obtained. Proof of sending the application does not guarantee coverage.
Can I simply send new documents after refusal?
Additional evidence may be useful, but the challenge route and deadline must also be preserved. Have the precise effect of the proposed submission checked.
Contact KM Legal to discuss your situation
Sources and references
Sources consulted on 6 November 2026.
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